How do i get better through the winter when i can't play in good conditions?

Right i am an avid golfer well from this year anyway :):) I have played golf since i was 3 and i am 16 now but the thiing is i haven't seemed to become great i am okay but not great and i think it is because i can't go to the golf course in winter because it's such bad conditions. I shoot around 85 to 95 in a regular round my best is 85 :) Except driving range is there anyway i can get even better for summer please help