Yes, try to play with friends or people you know that won't leave mid-round and play 18 holes. You get almost the same XP as a foursome for playing an 18 hole tournament too, so play in the weekly unlimited 18 hole.
You can always use energy drinks (I used a couple myself) but the really best way to level up is to play every day. You get a nice bonus just for playing consecutive days. When you figure out about what time your bonus kicks in get an energy drink right before that round too for another nice little boost. ;)