What do you do in RS?

It depends really, sometimes I can go crazy in a skill and just train train train it

I sometimes do that when I really want to get a certain level in a skill, then I usually end up quitting Runescape for a few weeks because I find it very boring after a while.
Now though, I just do whatever I feel like. Sometimes I decide to work on my goals and train one of the few skills I've got left to train. Other times I feel like killing things and I'll go train Slayer. Occasionally I might feel like testing my luck and go on a boss hunting trip and fail miserably with horrible loot.
It just depends on my mood really. Lately though, I'm really into skilling. It's quite fun watching your total level go up as you get closer and closer to your goal.