Waist cynchers, also called girdles, are used to help hold in tummies and accentuate curves or raise the breasts a little bit. They can also be used to help correct posture. In order to keep them from rolling up, there are a couple actions you can take, including buying a certain kind of waist cyncher and using materials to help them stick down.
Find a waist cyncher that has a flexible boning system along the front and back. This means that there will be thicker seams running perpendicular to your rib cage from the top of the waist cyncher down to the bottom. This boning will be key in making sure the cyncher does not roll upwards.
Slide the waist cyncher over you head. If it fastens down the front or back, make it as tight as you want it to look underneath your dress or shirt (or even your lingerie).
Soak a paper towel with extra-strength hold hairspray. Carefully lift up the bottom front of the waist cycher and pat between the area of your skin and the waist cyncher. Do this on the left and right side of the front and back.
Let the waist cyncher fall back onto your skin before the hair spray dries to help anchor the bottom of the waist cyncher.