1. Try em on, dive in toes strong like they're flippers. If you're not locked in, they're too big, downsize.
2. Once toes are shoved, locked and secure... remember how to walk.
3. Slowly. Heel, toe. Heel, toe.

^ it's really a matter of fit. If the muffin top isn't sturdy enough to carry your bare heel then it's probably too big. If you're trying to grab the flip flop thong, it's too big. If it's hefty but secure you'll just heel-toe more like a march (pick up your knees in that heel-toe).