Sprints. That'll condition you and trim off some of that fat you've recently obtained. As far as weights, I'm sure they'll help a little but tryouts are in 30 days. If you haven't been squating you might want to look into. There are soooooo many different exercises to be done, but I think it's wise to hit the weights hard in the "off season". Be careful of overtraining before tryouts as well as getting injured.
Eat healthy. You know lots of protien fruits and veggies. Drink a lot of water, a lot!