You may not want to add every song in your iTunes library to your iPod. While the default is to sync every song, it may not always make sense for you. For instance, your library may be bigger than your iPod's capacity or you may have holiday music that you want to keep but not bring with you all the time.
There are two ways to only sync particular songs: by unchecking songs or by creating playlists.
1. By unchecking songs
In order to sync only the songs you check in iTunes, you must first connect your iPod to your computer and go to the iPod configuration window.
Check "Only sync checked items"
Make sure that this option, at the bottom of the page, is selected. Once you've done that, be sure to click "apply" at the bottom-right corner.
Click the music library icon at the top of the left-hand column in iTunes. This will bring you back to your library, where you can choose what songs you don't want to add to your iPod.
Next to each song in iTunes is a little checkbox. When you turn on the "Only sync checked items" option (as we did in step 2), any song with a check next to it will be added to your iPod. If you uncheck that box (as highlighted in this image in green), the unchecked songs will not be added to your iPod.
If the songs are already on it, they'll be removed the next time you sync. You can always add them back by just checking the box next to the song.
And that's how you exclude songs by unchecking them.
2. By using playlists
To only sync certain songs using playlists, you must first create a new playlist. Once you've done this, drag all the music you want added to your iPod to the new playlist.
Then, with your iPod connected, go to the iPod management window. Select the "music" tab.
In that tab, choose the "selected playlists" button and then choose the playlist you've just created and nothing else. This will ensure that only the new playlist you've created will be synced to your iPod.
Click the "apply" button at the bottom right and you'll be all set.
Resync your iPod and all the changes will take effect.
After you do this, you must remember that only music added to your new playlist will be transferred to your iPod; additions don't happen automatically anymore. This means that whenever you add a new CD to your library or buy from the iTunes Store, you have to manually add those songs to your new playlist
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