Find "ringtones+sounds"
Slide your finger left on the display.
Press Settings.
Press Settings.
Press ringtones+sounds.
Choose message tone
Press the field below "New text or IM".
Press the play icon next to the required message tones to listen to them.
Once you've found a message tone you like, press the required message tone.
Return to the home screen
Press the Home key to return to the home screen.