Open the Settings app
Tap Sound and vibration or Sound
Tap Phone ringtone
Select a ringtone from the list
Tap OK or Save if prompted
To set a custom ringtone, tap Add ringtone or My Sounds if available
Choose the audio file you want
Confirm your selection
To change notification sounds, go to Settings
Tap Sound and vibration or Notifications
Tap Notification sound
Select a sound and confirm
To change alarm sounds, open the Clock app
Tap Alarm
Select an alarm
Tap the current alarm sound
Choose a new sound and save
To set a ringtone for a specific contact, open Contacts
Select the contact
Tap Edit
Tap Ringtone
Choose a ringtone and save