Drafting & tracing
Tracing a pattern instead of cutting it is what lets you sew the same pattern in two sizes. We compare pattern paper, tracing materials, curves, grading rulers and weights.
The transparent curve for armholes, necklines and hip lines. One reference on every Amazon store we checked.
Trace the pattern, cut the tracing, keep the original. One reference on every Amazon store we checked.
Best for: Anyone who cuts between two sizes, which is most people
Trace it, every time, on a multi-size pattern. Cutting condemns every other size permanently.
Transparent tracing paper, tissue paper or a non-woven pattern material. The non-woven survives folding and keeps better.
The test square must be measured with a ruler before any assembly. Printing at 95% gives a garment one size smaller.
From the pattern's measurement chart, not from shop sizing. The correspondences vary a great deal between publishers.
It depends on the publisher, and forgetting is a frequent cause of a garment coming out too small. The instructions always say.
On a fitted garment or an expensive fabric, yes. A toile in cheap cotton avoids ruining the final fabric.
Flat or rolled in labelled sleeves, never folded tight for years. Sharp creases distort the lines.
Trace, never cut a multi-size pattern: cutting condemns every other size. Measure the test square before assembling a printed pattern, and check whether the seam allowances are included — the most frequent cause of a garment coming out too small.