In sleeping position
Lie on a flat surface. Tighten the muscles on top of the thigh as tightly as you can. Then, pull your toes back, and push the back of the knee down to the floor. Now, you need to push out and up through the heel. Pull these back for 10 seconds, and try to tighten the muscles and relax for 5 seconds. Then, repeat it 10 times. Take a few seconds rest in between these steps.