Instructions
Launch StepMania and press the "Enter" key when the game screen appears.
Select the "Options" menu from the main menu list.
Select the "Configure Key/Joystick Mappings" option and press "Enter."
Select the key you wish to change and press "Enter." Push the key you wish associated with that action. If, for instance, you want to bind the "left" action to the left arrow key, select "Left" and press "Enter," and then press the left arrow key. Do this for all the desired keys, and then press the "Escape" key to save your changes and exit the menu.