- Make sure to COMPRESS your recording (Garageband, Audacity).
- EQ your track if you need to balance the bass/treble parts of the recording (Audacity).
- Add REVERB if desired (Garageband reverb is best).
- Add AUTOTUNE if desired (Garageband).
- Stack your track (copy+paste in Audacity or Garageband).
- Add different effects to each stacked track (Garageband, Audacity).
- PAN tracks to the right or left- especially Ad lib or backup tracks.
- As a last resort, turn up/down the GAIN (+ - in Audacity, volume in Garageband) to balance tracks.
How to move tracks from Audacity to Garageband:
- Select the track you want to export (the vocals, for example).
- Select FILE --> EXPORT SELECTION
- Export the file as an mp3, save somewhere quick like Desktop.
- Start Garageband, drag mp3 file into project.