How to treat a second degree burn on my leg?

While I was at a race track, I was riding a 110 dirtbike. I crashed and now I have a 2 degree burn on my lower leg and it is very large. How do I treat it? At first, I put neosporn and then square cloths and then wrapped it with gauze for school then unwrapped in when I got home. When I took the cloth of it would hurt and peal my skin off and make me bleed a lot. My cousin told me to put the medicine on the burn, put the suran wrap on my leg, wrap it up for school and when I get home, unwrap it. Many people said to stop doing that because it is bad. How do I treat my burn the right way? Is it really bad to do what my cousin told me to do by using suran wrap? Please and Thank you to all.