With mail, it's meant to be
mail($to, $subject, $message, $headers);
Try something like this:
$to = "youremailaddress@whatever.com";
$subject = "Your tickets yo";
$headers = "From: someone@someone.com\r\n";
$headers .= "Reply-To: someone@someone.com\r\n";
$headers .= "MIME=VERSION:1.0\r\n";
$headers .= "Content-Type: text/plain; charset=UTF-8\r\n;"
$message = "Nice tickets bro.";
mail($to, $subject, $message, $headers);
And please I hope it's just for example purposes, but please don't actually be sending it to admin@gmail.com
because obviously (unless you ARE actually admin@gmail.com
, you wont recieve the e-mail.