Adjusting the faders while mixing can end up a cyclical process. It’s easy to overdo it with faders. Instead of judging the quality of each adjustment on the spot, try what Roey Izhaki calls the Extremes-Inward experiment. By having a rough idea of where each fader should be, you can avoid over- or under-adjusting any of the tracks.
You an read the full details here: http://audioundone.com/working-with-faders