Choose your recording software and install it on your computer. Also called sequencers, these programs capture, process and edit the audio signals that you send to your computer, enabling you to craft a high-quality audio recording. Choices are many, and choosing the right one for your situation is largely a matter of personal preference, although there are certain brands that will work only on a PC and others that are designed specifically for a Mac, so a little research is in order (see Resources for a comparison chart).
Pick a digital interface. This is a piece of hardware that will enable you to get your audio sources into the computer. This connects to your computer via USB or FireWire, and you then plug your guitars and keyboards directly into the interface. Many of these interfaces have built-in preamplifiers that boost low-level signals (such as those from vocal microphones) to the desired level for recording. If you're recording solo, then a simple and inexpensive interface with a pair of inputs will suffice, whereas recording an ensemble will require a multi-channel interface that costs significantly more.
Open your recording software and plug your instrument of choice into the interface. Set your recording level, making sure that your signal isn't too loud or you'll produce digital distortion, also known as "clipping," which is a harsh, unmusical sound that should be avoided at all costs. With your level set, record your part, and then click on the playback button to review what you've recorded. If satisfied, you can repeat the process, adding new instrumental and vocal parts to build up your song in layers. This process, known as "overdubbing," allows you to create a full band production all by yourself.
Mix your song. This is the process whereby you listen to the instrumental and vocal tracks you've recorded, and adjust their tone and volume levels so that when they're all playing at the same time, the result is ear-pleasing and cohesive-sounding. The sequencer will also allow you to add effects such as reverb to your mix. Reverb replicates the sound typically made when recording in a large room, and gives an airy, space-like feel to your tracks.
Save your mix, and then burn it to an audio CD using your computer's CD burner. Your CD burning program will give you the option of burning a data, MP3 or audio CD. Choose the audio option, as this will give you better audio quality that will also play in most CD players. Be sure, too, to make extra backup copies of every song you record and mix. If you send out your only copy of a song and your computer crashes, you may have to completely rerecord your song.