Picture im media. This mistake is pointed out by many people if you make them. So a tip from the book: replace your or you're with you are to check. If the sentence is correct, use you're. If not, use your.

Examples:

● Mary is going to your party. √
(Mary is going to you are party is wrong. Therefore, your is correct.)

● You're going to start the test in five minutes. √
(You are going to start the test in five minutes is correct. Therefore, you're is correct.)