Are you worried about space? From what I know of mazar it's 100% indica so I wouldn't worry too much if you have height restrictions or something like that. If you're just looking for a better yield, then I always wait until it's at about the 4th or 5th node to top. Not all plants take well to topping though, so in the time it takes for the plant to grow another node or two find some info on your genetics.

Tying down will promote side growth much like topping it will, but you will still have your single dominant cola. Where as with topping you will get 2 or more colas with out the dominant hormone.