But what steps do I take. When I first start off I obviously dont have a railgun so which turret do I use up until I can use a railgun?

lol made mistake, and yes i do know that

What are the exact steps I should take in order to have railgun M0 and wasp M2 or M3 as soon as possible. Until I have the necessary rank for railgun, do I use smoky, twins or firebird?. Hunter or wasp? and how much do I upgrade them or should I first upgrade my turret? Can a railgun M2 or M3 equipped with a wasp M2 or M3 beat anyone?. Can I usually win on any map with any ranks?