Stand up straight with your back to a wall.
Your legs should be approximately hip-distance apart.
Move your weight over onto one leg, holding your other leg in front of you.
Leaning against the wall for support, rise up onto the ball of your foot, lifting your heel from the floor.
Control the movement as you lower back down and repeat.
Ensure you keep your leg straight by clenching your thigh and buttock muscles, and look directly ahead.