Mixing is the process of getting the right tones and volume levels for each instrument (or track) in a multi-track recording and then creating the perfect blend of all of them to make a single harmonious song. It can be an incredibly arduous task, but the result of having a mix you like will make it well worth your time.

Drums

Begin with the drums. Figure out what type of bass drum sound you want and what type of snare drum sound you want. Avoid triggers and effects unless you feel that they're absolutely necessary. It's usually better to leave the natural sound of the drums in the mix. Turn the EQ (equalizer) higher or lower in accordance with the type of sound you're going for. You may want to begin tweaking the EQ lower on the bass drum and a bit higher on the snare drum until you find the sound you want. Low bass drum EQ will make for a deeper, more classic rock sound, while turning the EQ up a bit will give it more of a punch like the drums heard in modern songs. As for the snare, a low EQ will give it a flatter, wider sound, while turning up the high EQ can give it a tighter, higher-pitched sound. It's all a matter of balance, however, as turning up the low or high EQ too much on either end--for either part of the drums--can make them sound strange. Bring the cymbals into the mix next, but watch the high end. Having too much high end in cymbals can make for an annoying mix. Let them accent the power, but don't let them become too loud.

Bass

Bring the bass guitar into the mix next. Watch the tone of the bass to make sure the low end isn't mixing with the bass drum too much. Tweak the EQ beginning from the middle and slowly going lower until you find the bass guitar and drums meshing together to the point of becoming muddy. Bring the EQ slowly back up to the middle or high from that point. Close your eyes when you're bringing levels up and down so that you focus on the sound and not whatever is on your computer screen.

Guitars

Bring your guitars into the mix next. The type of guitar sound desired will be different for every person, and each mixer is going to want them nearer the front or back of the mix (louder or quieter) to varying degrees. Assuming it has all the proper effects on it (you should have done this before you began mixing), bring it slowly into the bass/drum mix, again closing your eyes and listening to the sound of the mix.

Vocals

Bring the vocals up slowly. The vocals should definitely be in the front of the mix, but how loud they are is up to you. Many pop bands/artists have vocals dominating the mix, while rock bands usually have them mixing pretty well with the music. Ask yourself, when bringing them into the mix, "Can I hear every pronunciation of every word?" You may not be able to understand every word, but there shouldn't be a single syllable that's being left out of the recording. Use a vocal compressor in your digital software to smooth the vocals out. The compressor will make the quiet parts a little louder and the loud parts a little quieter. Put your final mix onto a CD and take it out into your car or your home system. The mix should sound similar no matter where you play it. Some systems will have more bass than others, but the overall feel of the song should remain consistent regardless.

Source:

Musictweak.com