How do you "go with the flow" with someone you like without landing in the friend z

So I've been talking to this guy for the past two weeks and I feel as though there could be something there between us. The thing about him is that he likes to get to know someone really well and become good friends with them before taking it to that next level, which is great and I'm totally into doing that, but my only thing is that while, I'm fine with going with the flow, I'm afraid that I'll find myself in the friend zone. Obviously don't want that AT ALL!

So, how do I go about "going with the flow" with him without landing in the friend zone and being clear that along the way, I'd like to be more than friends?