All measurements should be taken while standing with feet shoulder width apart (note that the figure in my sketch is standing with its legs a little too far apart). The arm length should be taken with the arm at your side, elbow bent. If at all possible, get someone to assist you. Measurements shown with arrows > > indicate that the measurement should go all the way around the body and meet back at the starting point.
2: Shoulder to Ankle
5: Waist (natural waist, not necessarily where you wear your pants.)
6: Hip (over fullest part of your buns and hips)
7: Inseam (crotch to ankle)
9: Arm length (base of neck to wrist)
For coveralls, like pilot flight suits, I also need a "torso" measurement. This measurement goes around the shoulder, across the chest, between the legs, up across the back, and joins at the starting point. See the sketch below:
(Click on image for a larger view)