What they said - plus, just focus on getting over the step initially. Don't worry about actually kicking your butt - just get the feel for getting your feet over the step each time (this one actually scares me - I always feel like something is going to go horribly wrong and I'm going to hurt myself). After you've mastered that, you can start aiming to get your kicks closer to your butt each time. Then, raise the step height. I'm still at the low step, just get over it phase myself, so I'm right with you!!