For the in-game instructions, press the "instructions" button and click to change slides. - Use the Arrow keys to control Fireboy and the "ASWD" keys to control Watergirl. - Get the gems of your respective colors, and then go to the door that will appear. - Avoid the red or you will have to return to your starting point. - Blocks or shapes of the same color are portals, and will bring you to the location of the other block.
After finishing a level, press v and b at the same time for the unbeatable level. It is pretty glitchy.