How do i receive a message?

So what i want to do is, once the character touch the button, the tile changes, so my code is here

this is for the Button:

function OnCollisionEnter (myCollision : Collision) {
if(myCollision.gameObject.name == “ButtonRed”){
SendMessage (“tileRedChanges”);
}
}

this is for the Tile:

**if ( something happened… lol… i don’t’ know what to write here and somewhere else to receive the message)
{
transform.localScale = Vector3(3,1,58.70655);

	transform.position.x = -42.27357;

	transform.position.y = 5.5;

	transform.position.z = 134.2756;
}**

just wondering how can i write a receiver of the message it sent from the button?

(why the first part of script look like this…)

The receiver of the message is a function you write that has the same exact name as the message, so make a function called tileRedChanges
And read this: http://unity3d.com/support/documentation/ScriptReference/GameObject.SendMessage.html