You have plenty of choices for how to make your iPhone unique: you can change the wallpaper to your family portrait, arrange the home screen by color of app icons, or perhaps add your own ringtones. Follow the instructions below and you'll see how to create a ringtone from any song in your iTunes library, for free. But please, don't set it to Gangnam Style.
Step 1: Select your song
Right click and select Get info
In iTunes, find the song you want to use for your fancy new ringtone. Right-click and select 'Get Info'.
Step 2: Set a Start and Stop time
Navigate to Options
Once you're in the info view, navigate along the top to Options and from there you must select both a start and a stop time. After some fiddling around with the track to find where exactly you want it to start, you can trim it down, and then click OK - remember it can't be longer than 40 seconds.
Step 3: Creating an AAC Version
Convert to AAC Version
Next, right-click again on the track and click on Create AAC Version. This will automatically duplicate the track, and will create the file you will be working with from now on. You'll notice a difference in the time of the track compared to the original. You'll probably want to go back to the original file and remove the start and stop times of the song if you want it to return to normal.
Step 4: Converting to a Ringtone
Right-click and choose "Show in Finder"
You next need to locate to file of the track, and to do that you should right-click on the new version, and chose Show in Finder.
The new AAC Version and the original track
This should present you with the track name, with a .m4a extension. We need to rename that to .m4r which is as simple as removing the 'a' and replacing with an 'r'. You'll get a popup asking if you're sure, click Use .m4r.
Click Use .m4r
Step 5: Deleting the AAC Version
Make sure to keep the file
Go back into iTunes once more, right-click and delete the AAC Version (the shorter duplicate of the original). Click Delete Song and Keep File on the popups.
Step 6: Adding to Tones
Finally, you should go back to Finder and double-click on your ringtone file (.m4r), which should automatically copy it to the Tones section of your iTunes library.
Your ringtone should now show up in the Tones section
So there we go, you can create ringtones from any of your iTunes music, all for free in just a few simple steps. Now you can annoy your friends with witty tones and enjoy your very personalized phone whenever someone calls.