What should I do in runescape?

I would say mage is most fun but not the easiest. If you go with melee work on your Attack for a better hit rate. Strength if you like higher damage or Defence for tanking. I myself would work on wood cutting first. Boring? Yes. but it is all worth it in the end, you have lots of money to spend which you will be needed if you are a ranger for arrows or mage for runes. Cut willows until you are able to cut Yew, and cut yew all the way to 99 or alernate between yew and mage logs. mage logs last time i checked are 1.1k for 1 log. good money. also rune crafting for mage too.