I think my hairline is receding. Help?

I just turned 17 years old, I'm male, and I think that my hairline is receding. It seems like when I don't get a shape-up or anything for a while, it starts to look like that. But, I really think it is receding and I really want some help on how to stop it and make it better before I get older and lose it all. Please give me legit answers. Thank you.