Set all the sliders flat. By starting with no equalization, you can hear the music or sound you will be working with in its natural state.
Cut the frequencies that you feel are necessary. Start by making large changes to the equalizer through cutting bands to see which changes sound the best. This will let you know where to begin making small cuts to affect the sound to tailor it to the room acoustics.
Boost to extremes as well to see what you what frequencies are harsh. You will find frequencies that when you boost to the extreme sound horrible, this is one way to know what not to boost when you fine tune your equalizer.
Boost and cut the frequencies that you found necessary to adjust in small amounts accordingly. By boosting and cutting the good and bad frequencies earlier, you know where to begin to fine tune.
Switch between the equalization you have decided on and the bypassed sound. You want to make sure that it sounds better when the equalizer is on and if it does not, you must find the bands that are problematic and cut or boost them accordingly.