well those tactics are different usable depending on which hero u have...so u cant have THE perfect strategy.
if u play as sonic,get his passive first and then his fire walk.(i really recommend to buy some boots as early as possible)
his norm attack gets a nice boost early in the game with it and creeping around is alot easier.
if u play as robin:
take her mass roots skill at first!
creeps are kinda useless against this skill so its very easy to kill them =)