I like to start each semester of school by writing out my goals for the semester and clearly outlining what I want to change or accomplish that year. I keep myself accountable by making weekly goals and making sure that the things that will take me towards achieving my long term goals. Why do am I bothering to say all this? Because I think that this is one of the ways to make the most of your semester.
Ask any college student about how fast college goes and almost all of them will agree that the semester really flies by so making the most of every day, every class, every friendship, every event, and every opportunity is extremely important. Don't take advantage of the time you have in college because it will be over as soon as it started as you will regret not enjoying those things while you had the chance.
Say yes to opportunities that scare you. Pick up a new hobby. Take a class that interests you. Become friends with people who are different from you. You will appreciate those experiences when you leave college because you will learn things that you can't learn anywhere else.