How Can Penis Size Be Increased Non Surgically?

I am 22 years old and still a virgin. I have never allowed things to escallate with girls to anything sexual because I'm simply insecure about the size of my penis. My unerected size is 1.5 inches and erected is 3.5 which is well below the average I have read on the internet (3.75 unerected). Should I save and try to obtain surgery before thinking about becoming sexually active? is there any other way to increase size besides surgery?