You need to enjoy this time. You have studied and prepared for finals and now that it is over that means its summer and there is no school for 3 months.
1. You should do something fun with friends for that last time if you or your friends don't live in your college town. Whether that would be a day trip somewhere close to where you live. Or something even as simple as going to dinner or getting ice cream with friends. You could plan a fun activity like mini golf or painting pottery. Plan something so that when you are studying for finals you have something to look forward to when finals are over. This really helped me because it got me to see beyond my finals and be excited about something because who is actually excited about taking a final. It's always what comes after.
2. Get ready for summer! For this, you could do some shopping for some new summer outfits. Before this, you might want to go through that closet. This can be boring but also fun at the same time.
3. If you live away from home, going straight home after finals can be nice too. Seeing your family and friends that you haven't seen in months and probably haven't talked to in a couple of weeks because of all the studying. Pack up that dorm or apartment and head to the place you truly missed even if you don't want to admit it. We definitely have all missed our parent's home-cooked meals.
Now go do something fun we all deserve it. If your year was anything like mine you are so ready for this long break. Have fun and come back strong next year if you are continuing school.