Tap Apps.

Tap Messaging.

Tap the Menu key.

Tap Settings.

Tap Notifications to turn on the function.

When the box next to the menu item is ticked (V), the function is turned on.

Tap Select ringtone.

Tap the different message tones to listen to them.

Once you've found a message tone you like, tap OK.

Tap the Home key to return to standby mode.