You want to be moderately dry before wrapping a towel around you, so you can actively do things and move around without tracking water all over the place.
Women will most likely want to use a towel long enough to cover them from their upper chest to their mid thighs. Men may prefer to use a towel long enough to cover the area from their waist down to their knees.
Women should have the towel positioned higher on their back, so the horizontal top edge of the towel is at the height of their armpits. Men should have the towel positioned lower, at their waist, so the horizontal top edge of the towel is just above their buttocks.
For women, this wrapping will be across your chest, above your bust and parallel with your armpits. For men, this wrapping will be across your waist, parallel with your hips.
The more taut the original towel wrapping is, the more secure your towel wrap will be. Consider twisting the second corner and tucking the twisted portion into the top edge of the towel. This twisted portion may secure the towel even further. If the towel keeps coming undone, consider using a safety pin to keep the corner of the towel tightly tucked and in place.
