① first insert the data cable of the iphone (iphone5s) into the USB port of your computer, then open itunes (12.4.3.1)---Add the file to the library
② Select Music File--click Edit--Show introduction (G)
③ in the new page click "Options" to edit the music files, the general ringtone does not need to be too long, 40″ around on it.
④ Audio Production is complete, click "File"-"Convert (C)"-"Create ACC version"
After the ⑤ is created, the music list will appear in the new M4A file format of the music file, after right-clicking on the new music file, click "Show in Windows Explorer"-The new page appears
⑥ change the new file format from M4A to m4r in Windows Explorer
⑦ Select the Ringtone menu to drag the new music file from Windows Explorer into the ringtone. (If you can't, try changing the file to a directory)
⑧ Select the iphone menu to sync your ringtone. After syncing, you can change the ringtone in the phone's settings-sound-ringtone
iphone replacement for custom ringtones