Sart off with a few tangoes and boots of speed. If you are running low on mana and dont have anymore tangoes then buy some mana potions and salves. If you think you're not fast enough buy some power treads.
Try to get some kills so you can collect for the desolator. If you can't get any kills go farming. Or switch a lane. After you got the desolator go for the linken's sphere, and monkey king bar.
If you are dominating in the game or have less chance of death go for the divine rapier.