Just Try to play safe using this because if you dont you will die very quikly.
Try to assist your team from far, and use the dart when you can

Normally i chose bot using this set but you can also top or mid
Try to go with a lux, with her you will be able to farm enemy champions very easily

Always stay behind the minios unless your oponent is a melee champion and it doesnt have any kind of ranged skills.Try to be in the bushes so you can use the dart to slowly take health from you enemies