Hook the MP3 player up to your computer using a USB cable. Allow the computer to detect the MP3 device, then double-click the MP3 icon on the desktop (single-click it if you're using a Mac).
Click on "My Computer" and double-click the MP3 device if you use an older operating system that doesn't detect a new device.
Sync your MP3 player to your computer. If you haven't yet synced your MP3 player to your computer, click on the device icon and complete the guided process. If you select automatic sync, most MP3 players will download all the music stored on your computer. If your prefer to be more selective, sync your songs manually.
Open your music file library, click on a song and drag it to your MP3 file icon. Release the mouse button. Select all the music you want by dragging and dropping it into your MP3 player.