HOW: Set up a box of the desired height in front of you. Start with both feet on the ground. Using the momentum of your arms, swing them towards the ground while bending at your hip and knee. Then explosively jump up and onto the box. Make sure to lift your feet to clear the box.
FEEL: You will feel all the muscles in your legs working to control the landing and descent.
COMPENSATION: Landing Position. Make sure your knees are aligned over your toes. They should not dive inwards on the landing. Your goal is to absorb as much of the landing forces as you can and land softly. That means that you want your hips and knees to bend as much as they can to absorb the force. If you do not let them bend much, you will land "stiff" and hard. Let your hips go back and your chest go down to help absorb the forces. Your toes should touch the ground first when you land and quickly your heels will follow. You should land in a "ready position" like you would if you were playing sports, with your weight ever so slightly forward on the balls of you feet. You should not fall forward or backwards after landing.