There's a lot that can happen in four years. You tend to be a very different person, especially after some experience in the university world. This is:
Your Freshman vs. Senior Self
Freshman: Smirnoff ice and mudslides
Senior: Cheap wine. It's a fruit! ... Fermented grape.
Freshman: Every night out involved careful planning of the bar, your outfit, hair and makeup, and a full on photo shoot in the living room or kitchen before going out. Be sure to get the red cups in so your friends back home know you're having a great time.
Senior: You're so busy and exhausted, but you still want to go out. You hop into whatever you find that's clean, or raid your roommates closet. Heels? Hell no. Everyone at the bar is younger than you anyways, no need for those, and putting effort into how you look. Don't accidentally want to pick up a 19 year old. Flats, and the cheapest wine you can find is all you need.
Freshman: Your laptop works perfectly because you just bought it in the summer.
Senior: If it will even turn on, it's a good day.
Freshman: Ensure you attend every event as it is a new experience.
Senior: Ensure you attend every event because it's your last chance before the real world, ahhhhh!
Freshman: You wouldn't dream of going out without your roommates.
Senior: You see your roommates from Freshman year and avoid them like the plague; that didn't work out so well. Not a problem, you've made 100 other friends that you got to choose now instead of in first year when you were friends with whoever you were placed with in residence out of necessity
Freshman: Buy every textbook, the professor said so!
Senior: Textbooks? Ha! I'll go take a picture of every page in the library of the textbook and read from there. Paying for textbooks, rookies.
Freshman: Gain the freshman 15.
Senior: Finally work it off.
Freshman: Visit friends from high school at their university on weekends, or have them visit you.
Senior: Friends from high school? Yeah, haven't talked to them in 3 years.
Freshman: Too afraid to go introduce yourself to your professors even though your advisor said its a smart thing to do.
Senior: Still haven't ever gotten around to introducing yourself to your professor. Whatever, it's too late now.
Freshman: Yay! Can't wait to go home for the summer!
Senior: Maybe I'll just stay in my university town and live it up just a litttttle bit longer?
Freshman: See a cute guy in class, start talking to him.
Senior: Tinders been invented. No need for face to face interaction with guys. Swipe left, swipe right, left, left, left, right, right, right.