Waist - This is the soft area directly above your hipbone, but below your rib cage. Start measuring from your belly button, bringing it the whole way around your body. 

Hips - Measure the circumference of your hips. Starting at one hip, measure over the longest part of your buttocks, all the way around to where you started.

Inseam - This is the measurement of your inner leg, from your crotch to the bottom hem of the leg.