541371 Show me how to post message on facebook wall from android ap

Here is the deal.. I have an android app and facebook app created related for this app... All i want a programmer to help me do is... -Tell me how to add a FB button in my app -When that button is clicked post a simple message on FB wall with the game score... I want programmer to setup a time and tell me how to do this... Because i will not send my app files... We can do a [login to view URL] session... Max i can pay for this small change is $20 let me know if anyone can help me do this...