Using a games level editor (especially a very flexible one) is a great stepping stone on attempting to create you're on game 
Ahem...
YOUR
pronoun
1.
(a form of the possessive case of you used as an attributive adjective):
Your jacket is in that closet. I like your idea.
Compare yours.
2.
one's (used to indicate that one belonging to oneself or to any person):
The consulate is your best source of information. As you go down the hill, the library is on your left.
3.
(used informally to indicate all members of a group, occupation, etc., or things of a particular type):
Take your factory worker, for instance. Your power brakes don't need that much servicing.
You're
1.
contraction of you are:
You're certain that's right?