If you are tired of iPhone existing ringtones but refuse to pay for an iPhone ringtone from the iTunes Store, then why not create the custom one by yourself. Though Apple hasn't made the process easy because it wants to sell you the ringtones from the iTunes Store, you can follow our step-by-step tutorial to turn any song you like into a ringtone on your iPhone successfully.
Tips: If you want to make Apple Music as iPhone ringtones, you can convert Apple Music to M4R first.
Extra Tips for Music User:
M4B to MP3 - How to Convert iTunes Audiobook M4B to MP3
RE: How to Convert Apple Music to MP3
You can also directly download rigntones on your devices but if you tend to customize, here we show you how to make iPhone ringtones with iTunes 12.7 on a Windows PC. It's a very similar process in older versions, and on a Mac.
Step 1. Open and Update iTunes
On your PC, launch iTunes by double-clicking its shortcut. Then, click the "Help" option and select "Check for Updates" near the bottom of the resulting drop-down list to update your iTunes to the latest version.
Step 2. Choose a Song in iTunes to Use as a Ringtone
Click on the My Music tab. Right-click on the song you want to use as a ringtone and then select Get Info.
Tips: If there is no songs in iTunes Library, you can click "File" -> "Add File to Library" to add music files to iTunes.
Step 3. Cut your Favorite Part of the Song
Click the Options tab and then tick the Start time and Stop time boxes. You will have to listen to the track first and note down the time you want it to start. Keep in mind that iPhone ringtones continually run in 30-second (or less) loops, so don't make the part longer than 30 seconds.
Step 4. Create AAC Version
Right-click the song again and select Create AAC Version. iTunes will duplicate the track, but if you look closely you'll see that the new version is only thirty seconds long. That's the one we'll use for our ringtone.
Update: On iTunes 12.5, Create AAC Version is hidden from right-click menu. To create AAC version on new iTunes, click to choose the audio clip that you are going to make ringtone, then choose "File" > "Convert" > "Create AAC Version".
Note: Remember to go back to the original track now and untick the Start and Stop options, otherwise the track will only play that short section.
Step 5. Change the Extension
Right-click on the short ringtone track and click Show in Windows Explorer. Then single-click the file's name, and change the extension from ".m4a" to ".m4r." Click Yes when asked if you want to change the extension.
Step 6. Add File to iTunes
Add the .m4r file using the "Add file to library" menu option in iTunes.
Step 7. Sync your iPhone
Connect your iPhone to iTunes. Afterward, click the iPhone icon in the upper-left corner; select the Tones section in the left-hand navigation bar. Once inside click Sync Tones>Selected tones>then the track you've created. Finally go to the bottom right hand corner and click Apply.