Php contact form

hello
I follwed and uploaded the script on this site for a contact form. But it just say blarg, when I test it.
Here is the code of the mailer.php

<?php
if(isset($_POST[‘submit’])) {

$to = “”;
$subject = “Contact Form”;
$name_field = $_POST[‘name’];
$email_field = $_POST[‘email’];
$message = $_POST[‘message’];

$body = “From: $name_field
E-Mail: $email_field
Message:
$message”;

echo “Data has been submitted to $to!”;
mail($to, $subject, $body);

} else {

echo “blarg!”;

}
?>
have I filled it in correctly? all I have done is removed the email address in the first $to
I followed the instructions but I think I need to add more to this form. Can anyone help me?