Has your college coach not provided you with any type of training plan for this Summer?
The general rule for increasing mileage is to never increase by more than 5% a week, for college athletes though this can be a bit conservative rate to increase by.
I'd recommend increasing your weekly mileage by 5 every week until you get into the 60 to 70 mpw range. Back off on the pace some though as you increase your mileage, it will help your body handle the training load.
If need be after every 3 weeks of building you can have a non-build week where you just hold the last weeks mileage or if you're really feeling a toll on your body from the increased mileage take a recovery week where you run 5-10 less miles than the week before and after that return back to your building.
Hope this helps some.