How do I grow out my (ethnic) hair?

I’m mixed (half black), and for all the goods in it I have VERY thick, curly hair that grows… well it doesn’t grow. I have it chemically relaxed but the ends are still curly. It’s easy to straighten but breaks a lot and I have to cut it before it gets a chance to grow. It also has a lot of damage in the back around the top of my head.

I really want long hair again but my roommate says it’ll take till senior year for it to be nice and long (we’re sophomores in college now). I know she’s probably right but I don’t know what to do in the meantime. All I ever do it blow dry it curly (which just looks like a mess) and put it up. I was thinking about braiding it for the summer but I work at a restaurant (in the least diverse state in America) and can’t find any way to braid it so that it would look cute enough to work in. I used to have tracks but I work out a lot and the sweat messes them up.

I think I’m stuck, does anyone have any suggestions/tips on how to grow it out and still have it be functional in the meantime???