Pattern Making Basics

Prepare the body

• Work with a partner whenever possible and measure over close-fitting underwear or a thin base layer.
• Stand naturally with balanced weight, relaxed shoulders and normal breathing; do not pull the body into an artificial pose.
• Tie narrow elastic around the natural waist so every vertical measurement begins or ends at the same reference line.
• Use one flexible, non-stretch tape and record the unit, date and person measured.

Build a useful measurement set

Begin with bust or chest, natural waist and full hip. Add back-waist length, shoulder length, neck, across-front and across-back widths, armhole depth, upper-arm circumference, arm length, waist-to-hip depth and the required garment length. Mark anatomical landmarks before measuring so the front, back and side measurements relate to the same points.

Measure consistently

Keep horizontal girths level with the floor and the tape snug without compressing the body. Follow the body contour only when the chosen drafting system calls for it. Repeat critical measurements and resolve any discrepancy before drafting. Keep body measurements separate from wearing ease and design ease: ease is added deliberately during drafting, not hidden inside the measurement.

Quality check

Compare related dimensions—for example, full hip should correspond logically with front and back hip widths—and flag unusual results for re-measurement. The current ISO 8559-1 body-measurement framework provides standardized landmarks and terminology for clothing development.

Essential marks

• Cutting and stitching lines: distinguish the finished pattern edge from the line where the seam is sewn.
• Grainline and place-on-fold marks: control the orientation of the pattern on fabric.
• Notches, dots and drill marks: identify matching points, dart ends, pocket positions and construction checkpoints.
• Dart legs, centre line and apex: describe the wedge of fabric that creates shaping.
• Lengthen-or-shorten lines: show the controlled area for changing length without distorting the whole pattern.
• Centre front, centre back, balance lines and fold lines: record the pattern’s relationship to the body and garment.

Complete pattern information

Every working or production pattern should be legible without relying on memory. Add the style or project name, piece name, front or back, size, number to cut, fabric or lining designation, grainline and version information. Note whether seam allowance is included. Because symbol conventions can vary between companies and schools, always check the pattern key or establish a consistent studio standard.

Studio exercise

Create a one-page symbol key, then annotate a simple front bodice piece. Ask another student to explain the piece using only its markings; any ambiguity shows what must be corrected. Compare your key with the University of California 4-H pattern-symbol guide.

Draft the foundation

Use the measurement set required by your chosen system—normally bust or chest, waist, neck, shoulder, back-waist length, across-front and across-back widths, armhole depth and bust-point information where relevant. Establish square reference lines first, then locate centre front, centre back, bust or chest line, waist, neckline, shoulder, armhole and side seam. Add the amount of ease specified for the type of block you are making; a close moulage and a basic bodice block do not necessarily use the same ease.

Shape and true the pattern

Darts or equivalent shaping convert the flat draft into body volume. Smooth the neckline and armhole with the appropriate curve, then true adjoining seams so their stitch lines meet cleanly. Walk the shoulder and side seams, check the front and back lengths, square corners that must join, and add grainlines, balance marks and full labels. Preserve the master block without seam allowance unless your drafting system specifies otherwise.

Test the fit

Trace the block, add allowances to the copy and make a toile in stable woven fabric. Check that the shoulder seams sit correctly, side seams hang vertically, horizontal balance lines remain level, the neckline and armholes lie cleanly, and the bust or chest has the intended ease. Mark corrections on the toile and transfer them back to a fresh paper copy before creating the final master.

Learning outcome

You should finish with a clearly labelled, balanced block that can be copied repeatedly without losing the original. This block-to-toile-to-correction sequence reflects foundation patternmaking taught by the Fashion Institute of Technology and Parsons at The New School.

Draft the front and back

Start with waist, full hip, waist-to-hip depth and skirt length, then apply the ease required by your system. Draw centre-front and centre-back reference lines, waist, hip and hem levels. Distribute the difference between hip and waist through side-seam shaping and darts rather than forcing all suppression into one area. Dart placement, length and intake should reflect the body or size chart and remain balanced with the side seam.

True and label

Smooth the waist and hip curves, close each dart temporarily to true the waistline, and walk the front and back side seams along their stitch lines. Confirm that joining corners meet cleanly and that the hem is square to centre front and centre back unless the design requires another shape. Add grainlines, hip and balance lines, notches, piece names and cut instructions.

Fit the toile

Use a stable woven test fabric. The waistline should sit at the intended level, side seams should appear vertical, the hip should have the planned ease and the hem should hang level. Diagonal drag lines often indicate that length or width is missing nearby; loose folds can signal excess. Pin and mark one correction at a time, then transfer it to the paper pattern and re-true the affected lines.

Studio exercise

Make a half-scale skirt block and one full-scale toile. Keep the corrected master intact, then trace a separate copy for your first style adaptation. Basic bodice and skirt slopers, muslin testing and fit correction form the core of introductory courses such as RISD Continuing Education patternmaking.

Use connected measurements

Draft from the armhole information required by your method together with upper-arm circumference, sleeve length and any elbow or wrist measurements needed. Establish the sleeve grainline and centre line, cap height, biceps line, underarm seams and hem. The front and back cap are not interchangeable: preserve their different shaping and mark them clearly.

Balance sleeve and armhole

Walk the sleeve-cap stitch line against the bodice armhole from the underarm points toward the shoulder. Confirm the placement of front, back and shoulder balance marks and record any intentional cap ease. The correct amount depends on the drafting system, fabric and sleeve design, so it should be controlled rather than assumed. True the underarm seams and hem before adding allowances.

Fit and diagnose

Set the test sleeve into the bodice toile with all balance marks matched. Check that the sleeve hangs on the intended pitch, the grainline appears vertical, the cap is smooth, and the wearer can move without excessive pulling or twisting. Diagnose whether a problem belongs to the sleeve, the armhole or both before altering; changing one automatically affects their shared seam.

Studio exercise

Draft and test one basic sleeve from your corrected bodice, then annotate the final pattern with front and back notches. Carnegie Mellon’s garment curriculum similarly sequences bodice fitting, truing, transfer and sleeve-block development.

Understand the directions

• Lengthwise grain: runs parallel to the selvage and is the usual reference for a straight-grain arrow.
• Crosswise grain: runs perpendicular to the selvage.
• Bias: runs diagonally between the lengthwise and crosswise directions and behaves with greater flexibility and stretch.
• Place on fold: positions a pattern edge exactly on the fabric fold so a mirrored piece is cut without a centre seam.

Place the pattern accurately

Before cutting, make sure the fabric is relaxed, smooth and on grain. Measure from each end of the grainline arrow to the same selvage; the distances must match before the piece is secured. For napped fabrics, one-way prints or directional shine, keep all required pieces facing the specified direction even when a tighter layout appears possible.

Quality check

Draw grainlines long enough to measure accurately and extend them through any traced or altered copy. Recheck the grainline after dart manipulation, added fullness or style-line development. The University of Tennessee 4-H guide distinguishes lengthwise, crosswise and bias grain and explains their relationship to the selvage.

Studio exercise

Cut identical half-scale skirt fronts on straight grain, cross grain and bias. Hang them before sewing and record the changes in stability, drape and distortion.

Plan useful notches

Place notches at important balance points: matching seams, major curve changes, centres, yokes, panel joins, controlled easing zones and other construction landmarks. Single, double and triple notch systems can distinguish pieces or directions, but their meaning must remain consistent across the entire pattern set. Notches should identify information, not decorate every edge.

Check the pattern set

Walk adjoining stitch lines and verify that each notch has a precise partner. Position the mark perpendicular to the seam line and within the seam-allowance area so it remains visible without changing the finished seam. Sleeve patterns need especially clear front, back and shoulder balance references because the cap is asymmetrical.

Transfer safely

Mark notches before removing the paper pattern. Depending on the fabric and studio method, use a very shallow clip, an outward-cut triangle, chalk or a tailor’s tack. Avoid deep cuts that reach the stitching line or weaken a fabric that frays easily. University extension references describe notches as matching aids and show the common single, double and triple visual convention in the UC pattern-symbol guide.

Studio exercise

Walk the seams of your bodice and sleeve blocks, add only the necessary balance notches, and ask a partner to assemble the toile without verbal guidance.

Separate fit from construction

Draft, measure and true the underlying stitch lines first. A master block is commonly kept without seam allowance so its fit and seam relationships remain easy to read. Add allowance to a traced working or production pattern after the design lines are finalized. State clearly on every piece whether allowance is included.

Choose the width deliberately

There is no single correct width for every edge. The appropriate allowance depends on seam type, fabric stability, construction method, machinery, curve, enclosed finish and whether fitting adjustments are expected. Hems and facings may need different treatment from ordinary joining seams. Follow the project specification and record exceptions directly on the pattern rather than relying on memory.

Add and true the allowance

Create an even offset measured perpendicular to the stitch line. True corners and intersecting seams in their sewn position so the cut edges align after pressing or turning. Keep the cut line visually distinct from the stitch line, add notches after the allowance is established, and walk matching seams along their stitch lines—not their outer cut edges. When checking pattern measurements, exclude darts and seam allowances unless the exercise explicitly requires them.

Studio exercise

Trace one block without allowance, assign suitable allowances for a simple toile, add them to the copy and audit every corner. The Parsons patternmaking curriculum treats seam allowances, notches, fitting and pattern correction as connected skills rather than isolated steps.

Protect the fit

Work from a traced copy of a corrected master block. Mark the shaping pivot—often the bust point on a front bodice—and distinguish it from the final dart point. Choose a new dart direction that supports the design and construction. When the original dart closes, an equivalent opening must appear at the new position; changing the total intake changes the fit rather than merely relocating the shaping.

Use the two foundation methods

• Pivot method: trace part of the block, rotate the block around the pivot until the original dart closes, then continue tracing. The untraced area becomes the new dart.
• Slash-and-spread method: cut from the new position to the pivot, close the original dart and allow the new cut to open. Secure the pattern and fill the opening with paper.

Finish the new pattern

Redraw the dart legs and refine the dart point according to the garment, fabric and fitting result. True the seam with the dart folded as it will be sewn, restore the grainline and all labels, and walk any affected seams. One dart may be divided into several darts or converted into a style line, gathers, tucks or pleats, provided the required shaping is controlled and tested.

Studio exercise

On half-scale copies, move one waist dart to the side seam, shoulder and neckline using both techniques. Compare accuracy, then sew one version in muslin. Pivot and slash-and-spread are the two core methods identified in the Coast Colleges flat-pattern curriculum.

Choose the right copy

Keep the corrected block or sloper as the master. Trace a fresh copy for seam allowances, style development, fitting adjustments or size experiments. Use pattern paper and a sharp pencil with suitable tools such as a transparent ruler, L-square, French or hip curve, tracing wheel, awl or notcher. The method must transfer information cleanly without damaging the master.

Transfer every essential mark

Secure the layers so they cannot shift. Trace the intended stitch or cutting line, then copy grainlines, centre front or back, fold lines, darts, notches, dots, drill points, balance lines, pleats, lengthen-or-shorten lines and internal construction marks. Add the project and piece names, front or back, size, number to cut, material, seam-allowance status, version and date.

Audit the copy

Overlay it on the master to detect drift, then walk and true adjoining seams. Check that curves are smooth, corners meet in their sewn position, paired notches agree and the grainline has not changed. Use a different pencil colour for fitting corrections and create a new clean version after approval so the development history remains readable.

Studio exercise

Trace one master block twice: one untouched archive copy and one working copy for a design change. Complete a line-and-symbol audit before cutting. Carnegie Mellon’s learning sequence explicitly connects toile corrections, tracing and a refined pattern version.