6 Max or 9 Max for BR building (microstakes)

If you are brand new, I would recommend playing 9 max and learning the starting hand selections for each position (playing tightly as possible, playing a "nit" strategy is a good idea at the micros). 6 max allows you to play a wider range of hands from each position, as there are less players behind you to act, but it can cause you to make mistakes in hand selection. For example, A5 suited is a fine hand to be playing from the cut off, perhaps even high jack in 6 max, but you want to avoid that in 9 max most of the time.

agree with winspear and my advice will be to play TAG style. on 9max.

Simple answer: both are ok, 6max is more popular. The difference is that 6max is a bit more loose and aggressive. For me full ring tables are sooo boring that I started with 6max try both and figure out which one you like better.