Cut 15 feet to 30 feet of a soft, natural fiber line. Use a longer rope for a bigger person and a shorter rope for a smaller person.
Fold the rope evenly in half to form a loop -- or bight -- in the middle. Hold the rope by the loop.
Hold the bight just under the individual's navel and wrap the two strands around the waist. Pull the two strands through the loop and pull the rope so it sits snugly without hurting the individual.
Line the two strands of rope down the individual's center so they fall toward the ground. Tie an overhand knot at crotch level.
Bring the rope up between the legs toward the back and feed the two strands under the back rope and tie in an overhand knot. Ensure the rope isn't so tight that it hurts the individual.