Hmm, I'm not (yet! xD) a fursuiter myself, but I have cosplayed multiple times.
I would say, just have fun, is the main thing
These are just tips and things that came to mind. You don't
have to follow them, but it can help you ^^
If you get hot, try to show it to someone (by for example waving your hand in front of you mouth up and down, or perhaps telling someone). Or find a seperate room and get your head and/or suit off to cool down quickly.
If this is important to you: Stay in character. (You don't have to, of course, but perhaps you would like to)
Oh yeah, and if you see small kids or children, don't take your head or other parts of yoru suit off in front of them. Some people know/expect this will have a very negative impact on children. It's like a mascot from a theme park would remove it's head, as if he's suddenly decapitated or something. Or the kids realise such things don't really exist, and kids need imagination and belief in certain things. -
Makes sense?-