I just found out (realized...was told....) that you don't have to hit the main page to get the game. So the controls listed there aren't any help.
So, from the game's main page:
Use the arrow keys or wasd (really only the left and right arrows and the a and d keys) to move.
Use space to jump.
Or use a joystick.
Wall jumping is possible, and necessary!
You can practice your moves on the menu screen.
Enjoy!