Use an electric keyboard with multi-track programming function capability to record the entire song including all the verses and choruses. Begin by recording the first layer of your song. This track typically includes the drums and rhythm section. All keyboards come with a built-in metronome, which will tick on an infinite loop. Set the metronome to the speed you want the song to be by adjusting the "beats per minute," or bpm. When you have the metronome timed at your desired rhythm and bpm, play the chords of the song over it while recording the first layer of your song.
Go back and listen to the first layer to make sure it came out the way you want. This is an important track because the entire song will be based on it. Make sure the changes between sections are on time and that you have stayed "on rhythm" throughout the song.
Use the keyboard's pre-programmed beats to substitute for the plain sounding metronome. Do not change the bpm setting when adding beats because you want it to match the first layer of the song perfectly. Add this second layer by recording it onto its own track and muting the metronome function.
Add a bass track. This is a crucial instrument for achieving a wide range of tones throughout the song. If your first track is piano, for example, the bass will bring out the lower frequencies and create a much fuller, rich sound for your piece.
Add more percussion. Most keyboards come with multiple percussion tones, which play the sounds of different drum pieces when you hit the keys instead of notes. This is a great way to add your own rhythmic flare, such as drum fills, to your song.
Add additional tracks as desired. Once you have a solid first layer, start adding other instruments to fill out the sound. This might include a horns section, stringed instruments such as violin or orchestra, or even more percussion to bring out the beat a little more.
Set the tempo and rhythm. Creating loops is essentially the same as composing a full song, but is much less time consuming. This is because with each track you add it is only necessary to play it for the length of the loop, which may only be 10 to 15 seconds, rather than the length of an entire song, which could be several minutes. The only down side to looping is you cannot easily create multiple sections to the song. It is, however, a great approach to composing verses and choruses individually and splicing them together later.
Record the baseline track with the metronome and rhythm section. When looping, it is critical to make sure this first track is properly timed because even a small mistake will be repeated over and over as you play the song.
Add additional tracks as desired. This is the fun part; add your own beats, string sections, trumpet solos or whatever else you can imagine.