I think you have to go into it knowing that things will change for you. You are now sharing your personal space and time with soemone else.
We all develope personal habits that best fit our lifestyle and we tend to get very comortable with those habits. The time we wake up, sleep, how long we spend in the shower, closet space, finances, what TV programs you watch, how late you stay up, meals, etc.
Be prepared to compromise and expect that you may be required to make changes. It's not a bad thing, it's just differnt than what you're use to.
Remember that he will also be doing/going through the same thing. When my partner and I moved in together, there wasn't any kind of official list or announcement regarding his or my expectations of each other. We sort of just let things happen. Initially, we devided everything equally. Cleaning, cooking, finanaces, laundry, shopping, etc. As time went on, we both realized that he was better at certain things and the same for me. For example, instead of alternating the cooking and cleaning, we realized that he was the better cook and I was better at cleaning up after meals.
Anyway, just expect that things will change and that it's okay. Go about your normal routine, and modify as you go along. Be patient and remember, he's going through it too.