Safely Sending Email from PHP - php

Question

I've got a page on my website where users can send me a message by giving their email, name, and a message. On the front end (JS) I do some basic verification, make sure the email is formatted like an email, make sure the other boxes aren't blank, and then I send it to PHP by GET.
Now I'm aware people can do some pretty sneaky stuff by injecting malicious code into PHP. What precautions should I be taking? When I was working with MySQL, I would escape it using the mysqli escape function. What should I be doing here?
Here's my script right now:
<?php
if(!isset($_GET["message"]) || !isset($_GET["name"]) || !isset($_GET["email"])){
echo "Check all the fields are correctly filled in and try again!";
die();
}
$email = $_GET["email"];
$message = $_GET["message"];
$name = $_GET["name"];
if($email == ""|| $message == "" || $name == ""){
echo "Check all the fields are correctly filled in and try again!";
die();
}
$message = wordwrap($message, 70);
mail("email#email.com","A Message From " . $name,$message,"From: $email\n");
echo "success";
?>

Answer 1

A very basic way is that you can declare a variable (for example $pattern)and store regular expressions (like patterns used commonly in attacks) in it, then use preg_match($pattern, $valueFromYourForm) method to see if any of the passed values matches any of those expressions and then you can stop the execution.