Use the arrow keys to move. Don't touch spikes. Click on the color of the character you want. You can change it at any time. Press the skip button to skip and the restart button to restart that level if you get stuck. On the level with the enemy targeted at you, it is meant to be glitchy to make it harder. Click on the arrow at the top of the screen and drag it down to see the message(the card) To make it applicable to you, remix it and then go to the message sprite's costume. Select all and drag it down so you can edit the words. Use this if you don't have a real card. It is quick and easy. Also, change the levels if you remix. You could just play it for fun too.
@okaythisisgood for an amazing platformer tutorial.