Ideas for leveling up faster?

I've had the game since launch. I'm only ranked 30. What are things you guys found best for XP? I don't care about the money or gold, I just want to rank up lol. I feel like I've played the game quite a bit but the leveling up and XP rewards are INSANELY slow. Showdowns are not that fun to me and stranger missions are all the same. All I want is the ability to buy all the cool clothes that are level required without spending my 80 gold haha