And I don't know if this works for everyone, but this is what works for me.
It is arguably true that too much bass in the cans can make you sing just a little bit out of tune, so take the bass down or out. I usually take all the instrument tracks down quite a bit. They're still audible, but only there for a reference . . . NOT to get a feel of the finished product. And I turn the vocals up so that I can hear myself clearly and distinctly. Make sure that your instrument tracks still have a decent balance, though. Just as an example of relativity (this is in no way actually to scale), if the instrument tracks are set at about 5, I'd set the vocals at about 10. And give yourself some good but subtle reverb to make it sound good to you (but not too much).
Really, I don't think there is a BEST way to monitor when tracking vocals. It's all about what works for you.
Hope I've helped
--Tax
