I'm not familiar with the flipout, but these instructions match what I've used on different phones.
https://motorola-global-e...8/~/flipout---using-musicTransfer using USB
Transfer music files from a computer to your memory card.
With a memory card inserted, and your phone showing the home screen, connect a Motorola micro USB data cable from your phone's micro USB port to a USB port on your computer. Your phone should show in the status bar.
Drag down the status bar.
Tap USB connected to select the connection.
Tap Memory Card Management to connect your memory card to your computer. You can't use the files on your memory card while it is connected.
On your computer, find "Removable Device" (your memory card) in the "My Computer" window.
On your Apple Mac, your phone should appear as a new drive on the desktop. If the drive does not appear, reboot the computer.
Drag and drop your music to a folder on your memory card.
Tip: To help manage your music, create a "Music" folder on your memory card.
When you're done, use the "Safely Remove Hardware" feature to finish.