how to put banners!

I had problems putting banners on my profile, but I followed someones directions, and I finally got them there. It worked for the ones that are there, but I tried to put another one there for another site, and it didn't work, so I just left it off my profile. I don't know why it wouldn't copy and paste, and yes I did hit enter before I saved changes, but for some reason it just wouldn't put the banner there. I tired it different times. It could be the code they gave me is wrong, who knows. Anyway, I do have banners if you wan to check them out. Well, good luck to you and happy mylotting.