In this last section, I'll listen through the track and make minor adjustments so that everything is clearly separated. Remember to listen to all the sections of your song back to back, so that you can hear if anything seems too quiet or too loud. If you, the person mixing feel that a part is obtrusive, you can be sure a listener who isn't familiar with the track will too!
A small tip, the human ear tends to percieve louder as better. That is usually NOT the case. Always be more concerned about the balance of the track, you can always raise the master volume of the entire piece later. I typically work with the mentality of "lower everything else" rather than "raise the volume of what I want to hear."
I hope these tips help in your pursuit of a great mix! Remember to be patient. Don't spend too much time on one track in a single session because you will wear your ears out and start making adjustments that aren't neccesary.