Learning how to mix music is an exciting skill to develop when you're producing in your own home studio. It's the time where all of the recordings you've made and all the parts you've created come together to gel into a whole piece of music. Mixing is definitely my own favorite time to be in the studio.
But it must be said that mixing can be one of the hardest skills to develop. It takes time and dedication to improve your skills, and you shouldn't expect to be a great mixer overnight. You need both creative and technical abilities to mix your productions - there's definitely an art and a science to the process.
There are lots of different ways to approach mixing in the studio. The main tool used is the audio mixer, which is used to balance and process all of the various tracks you have, resulting in a 2-track stereo mix at the end (one left channel, one right channel).
Most home producers start off mixing 'in the box' - mixing their tracks using software inside their studio computer. Whatever DAW you choose to use, it will likely have a mixing part to it.
If you want to mix your tracks on a real, physical mixing desk (either analog or digital), you'll be mixing 'out of the box'. I know many mixing engineers who prefer this way of working, but if you're setting up your home studio on a budget you probably won't have a desk to mix on (yet).
Either way, the ideas and processes are much the same for both forms of mixing. In fact, mixers who mix out of the box tend to also use tools that are in the box - an example would be to use a combination of Pro Tools for it's editing features, and then to send the outputs from Pro Tools into the inputs of a real mixing desk for the mixing session.
Before starting to mix, I always make sure that all the settings are 'flat' - that everything has been reset to zero (settings like EQ, sends, faders, input gain, etc.).
Inside your DAW, it's a good idea to arrange your tracks in a logical order. Have all your drum tracks placed next to each other, followed by your bass track(s), then guitars, keyboards, vocals, horns, strings, etc. Then you can organize them into subgroups.
An example I always follow is to group together my drum channels into a stereo subgroup (I often have around eight or nine separate drum channels). This still allows me to process each individual track however I like, but it gives me overall control of the whole group for parameters like volume with just the stereo set of faders.
If I want to bring down the volume of the whole drum kit, I can do it just by controlling the two faders of the subgroup on the mixing board, instead of having to individually adjust all eight channels. It also allows me to compress the whole drum kit together across this stereo subgroup.
You can apply this process to other groups as well - for example, you could bring together guitars or backing vocals into their own groups.
Whenever you're mixing your music, always make sure that your tracks don't go 'into the red' - that they don't clip or distort because the signal has become too loud.
When this happens in the digital domain, it can result in nasty and potentially harmful digital distortion. Adding effects to a channel can alter its overall signal level, so always be aware of where your signals are peaking.
There are a few different elements to a mix, and thinking of these elements can help you to get started and to focus on building the skill in each area:
All of these factors go toward learning how to mix music, and it's definitely worth developing your skills and techniques in all of these areas. Then you'll really be on your way to becoming a great mixer.