Division 3 baseball

I just graduated high school and I will be attending a division 3 school for college. I was wondering if anyone had any good advice on how to have good success and dominate the pitching mound

As a former D3 pitcher, the best way to to work really really really hard! Find your pitching coach day 1 of classes and set up weekly or biweekly pitching sessions. Get to the gym a lot, and just never give up.
For the most part your going to be facing better hitters than you ever have so be smart, and work on your control and breaking pitches.
Do not worry about velocity. Increased velocity will come naturally as you mature more.