Clean up all recorded tracks before mixing. Bring up the volume fader on the first track and listen to it in isolation so that any crackles, hisses and buzzes can be clearly heard. Audio problems such as these can be easily corrected with the editing tools on your recording software. Repeating this process for each remaining track will ensure that the tracks you use when mixing are as clean as possible. Random noises in the mix can be distracting, especially after repeated listens, so take care of them now.
Pull down the volume faders on everything but the drum tracks. If you used two overhead mics when recording, use the "pan" (panorama) control knob to place one of them hard left and the other hard right. Leave the kick drum and snare in the center of the mix, with the hi-hat and toms panned slightly left or right. Experiment with this placement and adjust the relative volume levels of all drum tracks until you have a natural sounding stereo image of a drum kit.
Raise the volume on the bass track until it blends with the drums. Keep the pan control centered so that the bass stays aligned with the kick and snare drum. Getting them to lock in together will give you a solid foundation on which to build your mix. If you have trouble hearing any separation between the kick drum and the bass guitar, experiment with the equalization (EQ) controls to create space for each of them to sit. If both tracks are competing for space in the same frequency, it can muddy the mix. Experiment with cutting or boosting different frequencies until you get the clarity you need.
Bring electric guitars into the mix, again using the pan control to separate them in the stereo field. If you have two electric guitar tracks, try panning one left and the other right. This will give them plenty of separation and adds a sense of width to the mix. You can now bring in other supporting instruments, like keyboards and acoustic guitars, sweeping their pan controls until you find the sweet-spot for each of them to sit in.
Bring up the lead vocal and leave it panned to the center. Feel free to use effects like reverb and delay to add a little sparkle and polish, and then gradually bring up the level of background vocal tracks. The key is to have background vocals support the lead vocal without overpowering it. When adding effects to the background vocals, try to use different settings than those on the lead vocal. Having the vocals all sound the same can lend a blandness to the song. Experiment too with the panning and EQ controls. By doing this, you'll find that you won't have to raise the volume to get separation from the lead vocal track.
Make any final adjustments to the relative levels, EQ, and panning of all tracks, and save as a stereo file in your recording software program. Then, burn this file to a CD-R using your computer's CD burner. As music is generally played on a variety of players, try to get an accurate idea of how your song really sounds by listening to it on your home stereo, portable player and on your car stereo system. Make a note of any audio shortcomings, and go back to your recording software to tweak and fine-tune your mix.