Ask your hosts if you can bring anything- or what you should bring.
Find out if they are stand hunters that sit all day, or if they move around and do some drives. Find out how "serious" they are about hunting- is it more of a social outing, or are they serious deer hunters that are there to shoot deer. Are they trophy hunters, or tag fillers? That will help you prepare.
Have layers of clothes...NO COTTON! You don't need underarmor or name brand, but get polyester underwear or athletic gear. You can get cheap stuff at Wal-Mart in the athletic section that is great. A fleece insulation layer above that helps, then your overcoats.
Chemical hand and footwarmers are cheap and help you sit longer.
A power bar or two (they can get hard if its cold), some water, and a sandwich..maybe an apple for a snack. I like to take a candy bar.
Wash your clothes in some kind of "free" detergent (Tide Free, All Free- whatever) or some baking soda. Hang outside on the line, and when dry, put it in a plastic garbage bag or a rubbermaid tub. You can dip your insulated boots in a tub of baking soda or free detergent, dry outside, then put in plastic bag and tub and you are good to go.
Its your first time hunting, so hit the range. Practice, practice, practice. Shoot at deer targets, not just circular targets. I wouldn't recommend shooting at moving deer. Know your effective range and don't shoot beyond it. One excellent shot is much better than 5 poor ones. A poor hit makes for a long track job, an upset stomach, and sometimes, a terrible regret. If you don't think you can make a quick, clean kill, don't take the shot.
If possible, have your buddy take you to your hunting area and pick out your spot ahead of time. Pick out some landmarks- a fence, a tree, a rock, a hill- whatever, that help you get your bearings on distances to help you with your maximum distance for shots, etc.
Lastly, if your buddies say "don't bring anything- we'll get it" don't show up empty handed. A case of soda, beer (for after the hunt only), some tasty snacks (beef jerky), or some other contribution will help ingratiate you to the group.
Be polite, enjoy the outing, and put the focus on enjoying yourself and experiencing the outdoors and not so much on "getting your deer".
Think about if you get one- if you have a truck, fine, but if you might have to bring a deer home in a van or trunk, you'll want to have some rope and plastic.
Gut gloves are a good idea, but also have a rag and some water along to wash up. I always seem to get blood inside the gloves or one of them breaks, etc. However, if your crew is decent, one of them will probably do your first one for you to show you how.
Keep your eyes open, and just take everything in.
