How do I get rid of a canker sore?

I'm an 11 year old girl and I've been getting them since I was smaller. They don't happen that often but usually about 3 a year and they are extremely annoying. I have one on the inside of my lip and it hurts sometimes. I put a medicine called Orajel Instant Pain Relief For All Mouth Sores and it really hurts when I put it on. Oh yeah, it started to bleed once but I didn't mess with it. I don't know why. Do you have any FAST things that will make it go away that DON'T HURT?! Thank you.