Sacred One:
Honestly, the key to mastering is listening to the track and making sure it sounds good. Thus, I can't necessarily take you step by step into mastering a track because there is no set way in doing so. The process depends on the style of music the song is and what kind of release it is to be...
Cool Edit Pro offers you the most utility for mastering the track. You want to mix your track first, and then save it as a .wav to be manipulated in Cool Edit.
Remember, you can't fix a bad mix in the mastering process.
There are a myriad of equalisers and compressors, that enable you to manipulate different frequency bands. I personally don't use Cool Edit, though I am familiar with it. However, these days, many mastered tracks are heavily compressed at the expense of dynamic range, in order to make the track sound as loud as possible.
Some basic things to consider to use are:
Split band compressors
Dynamic equalisers
Psychoacoustic devices:
Band Exciters
Exciters or Expanders for the overall mix
Obviously, if you don't know how to use these, you will destroy your mix. I can't help you on that, because I can't listen to the track, so you'll have to experiment yourself.
If you want to have a release for radio, there are mastering labs that should be able to do the track for you, because if you're new at it, it'll be a lot of trial and error. Also, you probably don't have the right monitors to work with for A/B references.
Also, make sure your track is in phase. Cool Edit has a function to analyse this. I wish I could help you out more, but you can't really master a track unless you hear it.
Sincerely,
God