Yichin, On a piece of paper draw a straight line level wth the edge of the paper. Then draw a line straight up. Divide that by two \ < That is 45 degrees. Straighten the knee An angle between the floor and your knee is at a right angle. As above we need half that distance. From a completely lowered position I can show an seven inch rise to my highest on step three. I think most could do better than that. Why not get somebody to measure yours. Keep the back straight and don't sit.Come down through the knees and lower the heel to the floor. One more thing the bending of the knee is to your front whether you are going forward or backward. For the lady the moving foot must be released, by about 9 inches Don't try to step back from a feet together position. Best of luck