How to put a mp3 ringtone to the iPhone 4 ?

[awesomeseekerdude999]

I am trying to put a mp3 ringtone to my moms iphone4 and it won't go to the ringtone folder. Its under 30 seconds which is the maximum length. Please help.

 

[Lol Fake]

http://mashable.com/2010/08/28/how-to-make-iphone-ringtones/

 

[Dylan]

convert it to M4A, then change the extension to M4R

 

[Caitlin.]

On my Verizon iPhone 4, once I sync the ringtone through iTunes to my phone. It's where you can pick a ringtone in sounds.