Here's a good way that works for me
Basically, you need to check it on as many different systems as possible, but that may not be posible for everyone. Below are ideas that most people can do.
Rule of thumb for me is this.
1. Mix it with good monitors if you got em. It's gonna sound pretty good from there alone. Just use whatever you have and get the best mix you can.
2. Then take it to your car. Make sure it sounds good like the radio or another cd. Study the track in your mind and isolate each sound to see if you can improve it. If you take it to your car and maybe a synth is too low, go back and remix it a little louder.
3. Make a cd of your track and play it on your DVD player and only listen to it through the tv speaker(s). Don't use a surround sound system to listen to it. I do high end video and graphics for DVD and Broadcast tv, and if you can get it to sound good on a tv at normal levels, you're on the right track.
4. Make a mono track and listen to it on speakers and headphones. You want to listen for any sounds that cancel each other out. If they do, go back and fix em. You can pan them, eq them or whatever you think is causing it.
Hope this helps, it's helped me in my productions.