Once you've found the right ringtone, you can either click "Download" or "Use Sound." The website will then send you a link to the ringtone's download page. Then, all you have to do is follow the instructions on the screen.
When you're done, you can then set the ringtone as your default ringtone or for a specific contact. You can also change the ringtone's volume to suit your preferences.
You can even set the ringtone to play automatically when you receive an incoming call or text message. This can be especially helpful for people who tend to forget to check their phones or have an unreliable cell phone connection.