If there were a shortcut to making a song "radio-quality", then thousands of pro recording engineers and producers would be out of work, hardly anyone would be attending Recording Engineering schools, and there would be no need for a Grammy for Recording Engineering Excellence - everyone's mixes would be great.
Not to be TOO pessimistic here, but recording engineers and producers spend years learning how things should sound and how to get those sounds. The mixes I made my first couple of years sounded pretty bad. Gradually, through extensive study, working FOR a pro engineer (and picking his brain), picking up tips on boards and in books, and lots and lots of practice, they now compete pretty well with everything but the megastar mixes.
Just try to make each mix better than the last one.
One thing I always do when mixing is import a commercial track from a CD into my session and solo it against my mix. That gives me a pretty good idea of how far I have to go yet. As far as the basics like signal flow, EQ, compression and reverb, there are a lot of good books around. The Owinski book mentioned by over-man is a good place to start.
I also highly recommend hiring someone to do your first few mixes. It will be a HUGE learning experience for you as well as get you a much better mix than you could by yourself.
It's all in the knowledge and the ears. Train your ears to pick out one thing in the mix and analyze it; and then make it sound better. Then find one more thing in the mix and do the same.
Here's a little secret: 50% (or more) of the quality of the mix/song is in the musicianship, and probably another 25% is in the arrangement itself. That leaves only 25% to the actual engineering - and I'm being generous to the engineering. Many feel that musicianship is 50% of a song and the arrangement is 40%, leaving only 10% for the engineering.
Dual 2.5Ghz 2004; 2.5GB RAM Mac OS X (10.4.8)
Dual 2.5Ghz 2004; 2.5GB RAM Mac OS X (10.4.8)