This is another one of those "dual care" piercings because it's both an oral piercing and a lip piercing and you have to treat each end of the piercing separately, following two sets of aftercare instructions. Eating and drinking are (obviously) greatly affected during the first week or so of healing, and smoking is a big no-no. Clear alcohol and wine are ok, but the yeast in beer really irritates these piercings so it's best to steer clear.
Recommended starter jewelry is usually a 16 or 14 gauge labret stud. They'll have to pierce you with an extra long one at first, to accommodate the swelling you'll have in the first week or two. That swelling will slowly go down as you heal, and after about 6 weeks, if you haven't had any problems with it, you can go back to your piercer for a shorter bar. This *should* be a free service that is included in the price of the initial piercing. Ask before you get pierced, so you know for sure.
Average healing time (for a healthy non-smoker) is about 6 - 12 weeks, but complete internal healing can take as long as 6 months.