Work on developing skills you need in life to be successful (whatever you define as successful).
I worked on developing analytical skills, relationship building/people skills, and sales skills. I felt like all great leaders needed to learn how to analyze situations, interact with people, and ultimately persuade people to do things they wanted such as join them, etc.
Realistically i had no clue wth i wanted to do in college. I just knew i wanted to run my own business and make a difference in the world. I didn't want to be stagnant so i continued studying business and slowly started working on developing my soft skills by volunteering, taking lower paying jobs that helped me develop my skills, and come interview time, i stated the story above and all my employers liked that even though i didn't know where i wanted to be exactly, they admired my clear focus of how i was positioning myself to achieve my goals.
You don't need to know EXACTLY what you want to do, but you will need to know they skills you'll need to develop to succeed. Nobody in the military knows exactly how bad the situations they're walking into are, but they prepare all their troops as best as possible to handle anything that comes their way. You should do the same thing.
