Basically you harass the other team till they rage quit.
You need teamwork because you aren't gonna get many kills by yourself and you are very squishy.
You want to make sure to give the your team mana this is one of your main jobs.
The other job is to push free lanes hard. You will want to be careful though because you are an easy target. However, on a lane completely by yourself, you can push very hard very quickly. Having boots of travel lets you get the quick push and then get out. You can also get back to your base quick to defend if your team is getting over run by creeps.