mp3 music-file-as-a-ringtone-on-my-samsung unable to set as ringtone
It should be quite easy.
Simply go to the music play on your phone
and press and hole on the mp3 you want to set as your ringtone.
Choose the option "set as" and then choose from one of the three options,
including "phone ringtone," "caller ringtone," and "alarm tone."