Stand with arms extended forward.
Squat down by bending hips back while allowing knees to bend forward slightly, keeping back straight and knees pointed same direction as feet. Descend until thighs are just past parallel to floor. Squat up by extending knees and hips until legs are straight. Return and repeat.
Keep head facing forward, back straight, chest high, and feet flat on surface; equal distribution of weight through forefoot and heel. Knees should point same direction as feet throughout movement. Arms positioned forward allows torso to be positioned more upright. See Squat Analysis.
Movement can be made easier by holding onto rails or back of chairs to each side. Alternatively, exercise can be performed by squatting down only part way. As strength increases, range of motion can be progressively increased.
For greater intensity exercise, light weight can be introduced. Alternately slightly more challenging body weight exercises can be performed.