Click the green flag. Mess around with the up and down arrows. Don't crash into a building.
I made this in 5 minutes so it's bad. Sorry. Meh. I was doing a challenge with someone to see who could make the best scratch game in 5 minutes. As you can see it kind of failed, but I won't make any edits to it as that would be cheating. Feel free to try your own 5 minute challenge!