Use The arrow keys or the W, A, S and D keys to move. View this as a test, this is not completed. There is a Level Editor which you can access by pressing the 0 key, and in the Level Editor, you can press 1, for layer 1, 2 for layer 2, and 3 for layer 3, if you press either of the keys 1, 2 or 3 two times, you will view either layer 1 if you pressed layer 1 two times, layer 2 if yo pressed 2 two times, or you will be able to view layer 3 if you press 3 two times, and press p in the Level Editor to see the collision pins
Thanks to Griffpatch for the tutorial