Exporting Your Voice/Dialog From Garageband to MP3

•  Record your audio in Garageband 
• Plug in headsets and click "Yes" when asked if you want to use C-Media USB Audio Device 
• Choose vocals you want to use
• Make sure you select C-Media USB in the Input
• 

• Record your vocals by clicking red circle at bottom
•  Record multiple tracks if needed.
• Click Share at the top of the screen
• Select "Save to Disk"
• Change Format to MP3
• Name sound and save it to Desktop or Music Folder
•  Add your audio in Flash using File>Import to Library
• Make sure all of your sounds are on different layers.