Basically keep on doing what you are, playing ranked stroke play games. As you get better your average will drop, when you have played enough rounds in each tier and got your average down to a predetermined level you will level up to Amateur, then pro, tour pro, master etc...
You may also try making some friends and playing with them, you can learn a lot of good stuff from seeing others play, also reading the FAQs and forums will also be very useful, especially
How to properly use chip and pitch clubs: A guide V2.0
Putting Tip: Distance Control