If you want to make your favorite song into a ringtone, you can import the music file into your iPhone at https://zigtone.com/iphone/. You can find this file in the Files application or on iCloud. Simply tap on it to copy it to your phone. From there, you can choose the name of the ringtone and make it yours. You can use your phone's Bluetooth connection or the USB port to transfer it to your iPhone. If you don't have any music files on your phone, you can also use Google Play Music.