Pack light but diverse. You do not need much beyond clothing and toiletries, but have a decent selection of clothes incase you travel.
Meet locals! It is very easy to only meet other study abroad students living in your building. Make yourself go out to pubs/bars/clubs and talk to strangers. You WILL regret it if you don’t.
Save your money. Drink some at home before you go out, make your own food, don’t eat out to much. You want to save your money so you can travel.
Take some days to relax and enjoy the town yourself. Don’t feel the need to push yourself every day. If you want to just walk around and enjoy the neighborhood you are in, do it. Makes it feel more like home as well.
DO NOT BE A STEREOTYPICAL AMERICAN. It is very easy to spot many American’s in Europe. You know the type of people I am talking about. Rude, loud, and poorly dressed with white socks. Do not be that person.