First remix the project(Don't worry it keeps instructions) Go to obby, than to costumes and design your level Make sure the costumes names are 1 and than the stage number example: 11, 12, 13, 14. If you want it to be added to the main game, make sure its at least 3 stages long, and at most 9 stages long, make sure you write that its a submission in notes and credits! There will be more instructions in the editor