Hi, I just got the game and there are a few things still perplexing me. I've pretty much got the general flanks army and kills infantry pretty much down, but before the battle, what does "Wait" do and how do you change the formation of your units? I've seen people say that sometimes you should use 3 ranks or string your units wide, but how do you do that?

Oh and while I'm here, how do you merge units together?

thanks