Talking about things before they happen is always the best. Both of you need to talk about boundaries (condoms, etc). The sooner the better.
Originally Posted by Morgan
(I'm trying to resist asking, mainly to avoid ruining her fun)
Why would asking ruin her fun? Communication is critical. You need to be able to talk to her openly and honestly. She needs to welcome your questions and give you honest answers. Does she have a history of lying?