SYNC MANUALLY IN WINDOWS MEDIA PLAYER

If you have a large music collection in your Windows Media Player Library or limited storage capacity on your portable device, it might make sense to sync your device manually. Each time you want to update the media on your device, you need to create a list of files and playlists to sync. If you want to create a random selection of songs, you can shuffle the list before you sync. Previously synced items will stay on your device until you delete each of them manually, or you can use the format feature to remove all previously synced data.
 

Syncing a device

For more information about automatically and manually syncing, see Set up a device to sync in Windows Media Player. For more information about the Player Library, see Getting started with Windows Media Player.

WINDOWS7,GETTING STARTED WITH WINDOWS MEDIA PLAYER

Windows Media Player provides an intuitive, easy-to-use interface to play digital media files, organize your digital media collection, burn CDs of your favorite music, rip music from CDs, sync digital media files to a portable device, and shop for digital media content from online stores.
Start Windows Media Player 
To start Windows Media Player, click the Start button , click All Programs, and then click Windows Media Player.