What should a Protestant do at Catholic M?

I was raised Methodist, however my dad's side of the family are very devout Catholics. He always went to our Methodist service, though. I was never taught that Catholicism was evil or anything, I've always just viewed them as Christians, like I do all the other denominations. Anyways, I was planning on going to the church my dad used to go to with my mom as we are both very interested in Catholicism. I'm hoping I can get him to come with us. My mom's always been intimidated by it; she says she'd never go unless my dad went to tell us what to do. But what are some things we should be aware of? Should we sit in the back of the sanctuary? Etc., etc.