Check out this post by Joe Gilder on homestudiocorner.com which is aimed toward those who mix their own music at home. He explains how to use a reference mix, or how to use a professionally mixed track with your own homegrown work as you are in the process of mixing. Joe includes a brief description of how he does this. He concludes with a link where you can find further information about the method.
Worth a read for all would be mixers this weekend:
A Boring (But Effective) Way to Avoid Embarrassing Mixes