How to change the message alurt thing on my pantech matrix c740?

I have a pantech matrix c740 when ever i get a text message from my friend or you know, it makes this annoying beep how can i change that to one from my Audio that i like pls helpHow to change the message alurt thing on my pantech matrix c740?if you just go into your sound profiles and edit it and put message on silent or vibrate.