Make sure no clothing items are blocking your waist when measuring. Stand up straight, hold the tape measure behind you, and bring it around your waist to meet at your navel. The tape should be parallel to the floor and fit snugly around your torso without digging into your skin. Give yourself some breathing room. Look at the place on the tape where zero end meets the other end of the tape measure. The location of this meeting point is your waist measurement. Double-check your measurement. Repeat the measurement once more to ensure the accuracy of your original measurement.
Depending on how you want to wear your waistbeads, you can measure yourself above your navel, just at your navel, or right above your hips.
Use a tape measure and measure against your bare skin without sucking in your stomach. You shouldn't hold the tape loose nor too snug.
Think about where you want to wear the beads. Underneath your clothes, around your navel? With a bikini, draped low at your bikini bottoms? With a crop top, sitting about your pants? Choose your size accordingly. Clasps are a popular option for those that want to remove their waist beads.