Designing and pattern making for lingerie is one of the more difficult areas of fashion due to the many curves, angles and odd measurements. Also your ability to be precise is tested during each step of the process. Make your own pattern for a bra that fits you just right.
Measure around your center bust line. Start at the side seam, go around the center of both breasts to the other side seam, and then around the back at the same level holding the measuring tape taught, but not indenting the flesh.
Get your bust point. Measure your bust point by holding the measuring tape tight from the center of one breast to the center of the other breast.
Figure your cup size. You want to measure from the middle of the shoulder to the bust point. Remember to do this for each breast as each one is a slightly different size even on the same person.
Measure your chest next, holding the tape taught from one arm pit to the other above the breast.
Take your underbust measurement the same way you did your bust line only at the underwire level.
Draw your larger sections with straight lines first. Use your ruler, right angle, and French curve template to set your measurements to paper. Add seam allowance to each line after you sketch each section.
Draft the cups next. Since the cups are the most rounded pieces, a template with various circle sizes can help give you the shape. Also use your French curve and right angle together to get the proper curve angle for each cup of the bra.
Sketch and re-sketch. There is a lot of room for error with so many curves and angles, so it is wise to draw, measure, re-draw, and measure again until you are confident your pattern is precise.
Test your pattern. Always create a mock-up of your pattern and see how it fits before using it with your final fabric. Designers have fittings for a reason and it all starts with the mock-up and adjustments are made from there. The same holds true here.
Have someone measure you instead of measuring yourself. Stand up straight in bare feet holding your arms to the side, and wear only a bra or nothing on top. Many patterns are simply adjustments of existing patterns. Another way to draft your bra pattern is to dismantle your existing bra, trace each section and make appropriate adjustments from there. This method is easier and quicker and it can give you an excellent starting point for drafting your bra pattern from scratch. Another method is to use drafting software. You type in the measurements and it draws your pattern for you. This is a good idea if you plan to make many bras for several people.