tea tree oil for pimples?

i used to have clear skin, i would get some pimples here and there but nothing too drastic. in february my skin started to go down hill. i started to get acne on my forehead and between my eyebrows mainly. i’ve popped them and have some acne scars, i heard that tea tree oil works. have any of you ever tried it and did it work? if so do i apply it directly to the pimple or do i have to dilute the tea tree oil with water?