The Bespoke Center shows how to measure the right sleeve for a custom made men's suit. The Center recommends using a tape measure of course to do your measuring. These recommendations are easy and work well for custom made DIY projects. For this project the man will need to wear a shirt. Measure from where the seam on the shoulder meets and to the base of your thumb located at the wrist joint. The tailor also recommends that you do this so that you can decide where you want the sleeve to end. Bespokes also advises that when tailoring, please be aware that there may be differences in the lengths of the arms.