How to read a sewing pattern: envelope, sizing, woven vs knit fabric and pre-washing

TUREFF• •0

A sewing pattern packs a lot of information into an envelope or a PDF, and it can look like a code at first. Once you know where to look, it tells you exactly what to buy, which size to cut and how to put the garment together. This guide covers reading the pattern, choosing a size and understanding fabric.

Reading the pattern envelope (or cover page)

Front: pictures or drawings of the garment and its variations (often called views).
Back: technical drawings showing the seams and details, which are clearer than the photos.
Size chart: body measurements for each size.
Finished garment measurements: the actual size of the garment once made. The difference between this and your body measurement is the "ease", the room to move.
Fabric requirements: how much fabric you need for each view and size, for different fabric widths.
Suggested fabrics: what the design was made for. Follow this closely at first.
Notions: everything else you need, such as zips, buttons, elastic and interfacing.

Choosing your size

Pattern sizes are not the same as shop clothing sizes. Do not choose by the size you buy in shops.

Measure your bust (or chest), waist and hips, with a tape measure held snug but not tight, over light clothing.
Compare them with the size chart.
If you fall between sizes, check the finished measurements and the ease to decide.
If different parts of you fall into different sizes, many patterns let you blend between size lines, for example from one size at the waist to another at the hip.
For a fitted garment, making a test version (a toile or muslin) from cheap fabric is the best way to check fit before cutting the good fabric.

Inside the pattern

Pattern pieces, each labelled with its name, number and how many to cut.
Grainline arrow: place it parallel to the fabric's straight grain (the selvedge, the finished edge). This is why garments hang properly.
Place on fold markings: the piece is cut on folded fabric to make one symmetrical piece.
Notches and dots: matching marks for joining pieces accurately.
Seam allowance: many commercial patterns include 1.5 cm (5/8 inch), but others use less, and some patterns do not include it at all. Always check the instructions.
Cutting layouts show how to arrange pieces on the fabric efficiently.

Woven vs knit fabrics

Woven fabrics are made of threads crossing at right angles, like cotton poplin, denim, linen and canvas.

Little or no stretch, except on the diagonal (the bias).
Fray at cut edges, so seams need finishing.
Easier for beginners because they stay put while you sew.

Knit fabrics are made of interlocking loops, like T-shirt jersey, sweatshirt fleece and rib.

Stretch, sometimes in both directions.
Usually do not fray.
Need a ballpoint needle and a stretch stitch or zigzag, so seams can stretch with the fabric.
Patterns designed for knits rely on that stretch; often the pattern states how much stretch the fabric needs.

Do not substitute a woven for a pattern designed for a knit: it may not fit over your head or shoulders at all.

Pre-washing fabric

Many fabrics, especially natural fibres such as cotton and linen, can shrink when first washed, and some dyes can run.

Wash and dry the fabric the way you plan to wash the finished garment, before cutting.
Finish or zigzag the cut ends first if it frays heavily.
Press it flat before laying out the pattern.
For dry-clean-only or delicate fabrics, check the care instructions from the seller.

Skipping this step is how a garment that fitted perfectly ends up a size too small after one wash.

Good first patterns

Look for patterns marked beginner or easy.
Choose woven cotton for the first few projects.
Elastic-waist skirts and trousers, simple tops and tote bags are classic starting points.
Read all the instructions before cutting anything.

Which pattern are you planning, or what part of the instructions confuses you? Ask in the comments below.