Altering a pattern to fit isn’t, in theory, all that difficult: Simply make the pattern’s dimensions match yours, plus some ease for movement and style. If you’ve struggled with getting the flat tissue to replicate your figure, it may help to learn how body parts relate to each other, and how the pattern represents the body.

The process requires accurate measurements. To get them, it’s important to establish reference points and lines on the body, so measurements are taken from stable locations that correlate to places on the pattern. We’ll show you where these key places are on the body, and how to find their corresponding points on the pattern.

Start with a fitting pattern

The pattern shown is for a basic sloper, often called a “block” or fitting pattern. It has few design features and minimal design ease, but it’s a useful tool to begin with when you’re figuring out how a pattern’s lines, curves, and areas are meant to represent the human form. You’ll discover where your shape matches—or doesn’t match—the pattern company’s standard size.

Because a pattern company’s fitting pattern is the basis for its fashion patterns, the information you gain from comparing your measurements to it gives you a head-start when fitting a pattern that includes design ease, style lines, and other silhouette-defining features. Once you locate the body’s important guideposts and know the distances between them, mapping your shape onto a pattern is much easier.

Measure the body and pattern

Mark, then measure, the body and the pattern. In each case, clear reference points and lines are essential. Some key body areas are nonnegotiable: the bust point and the fullest bust or hip circumference, for example. However, you can decide…