Started surfing a month ago.

I'm 15 and I started surfing about month ago. I live in Sydney and surf around Bondi beach and Bronte. My first board is 5'11 shortboard. I was sponsored in skateboarding and snowboarding in my country, before I moved here. So it was very very easy to start. I surf 3-5 ft waves and feel pretty confident on waves and a week ago did my first scetchy cutback. I guess it is pretty good already, but I really want to ride wave with more speed and use the whole wave, how to I achieve it?