hmm... I find it weird that whenever I try to answer something about the country I live in, I cannot think of anything as most things I do I take for granted as common universally.
But to help you the best I can without knowing much about Brazil or what you have done already. I would say first off get USD to replace the currency you are currently carrying (all the stores I goto don't accept British or Canadian coins I found, so I would assume Brazilian money would not be accepted either). Get a guide book of some sort so you know the best places to visit (alot of them come with coupons to). Book places to stay in advance.
I will edit/comment on my answer if I think of anything else (these are just the things that come to the top of my head)