How to send information from an html form to an array in php?

Question

I created an HTML contact form:

<section id="formulario">
<form action="assets/php/script.php" id="quaform" method="post">

<p class="textform">Nome Completo:</p>
    <div class="testeform"><input type="text" name="nome" size="50"></div><br>
<p>Email:</p>
    <div class="testeform"><input type="email" name="email" size="50"></div><br>
<p>Assunto:</p>
    <div class="testeform"><input type="text" name="assunto" size="50"></div><br>
<p>Mensagem:</p>
    <div class="testeform"><textarea id="caixademsg" name="msg"></textarea></div><br><br>

<input type="submit" value="Enviar" id="submitbutton">

</form>
</section>

And I can send you the information when I fill out the form this way:

<?php
$nome = $_POST["nome"];
$email = $_POST["email"];
$assunto = $_POST["assunto"];
$msg = $_POST["msg"];

$cont = 1;
$notas = array(
    'Nome' => $nome,
    'Email' => $email,
    'Assunto' => $assunto,
    'Mensagem' => $msg,
);

foreach ($notas as $key => $value) {
    echo "$key: ","<br>","$value","<br>";
}

?>

What I really want, is when I send 1 form, it gets saved on a page, where I can see it later, if I send 10 different formats, have the 10 formats on this page so I can see when I want.