If your attacking your opponents king, and you dont know exacly where to put the queen, put it on a square that is the same colour as the square your opponents king is standing on.
If your opponent has a knight on example f4, that you cant remove from the great post, put a biscop on f1.
Both are from the legend Bent Larsen.
when ever your opponent moves look at the squares that have been freed for new opportunities