When I compose music, I (almost) always do it in the following "steps":

Step one: I compose all the basics in the music, just like a sketch. I don't do anything in detail. I usually just make a simple rhythm, simple chords etc. I make the "skeleton".

Step two: I go into the finest little detail, such as making the drums more complex (if needed), vary the chords a bit more, adjust panning, Volume and effects. Adjusting small details in the lead, making intro and outro or looping-point. Maybe adding some more instruments/samples/ and even sound effects to the music. At this step I work pretty much with the stereo-impression.

Step three: Polishing the song. Changing very small details. I might let other people listen to get some feedback. I do small things like naming the song etc, etc.

Step four: I don't listen to the music for a period of time. That time can be from one day to two weeks depending on how much time I have (During this time I start to compose other music, if there is any.) When that time has passed, I listen again, with a "new ear" and then I might hear things I didn't notice before.

The song is finished =)

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