Something

<?php
session_start();
if (!isset($_SESSION['count'])) {
   $count = 1;
} else {
   $count++;
}
?>

<p>
Hello visitor, you have seen this page <?php echo $_SESSION['count']; ?> times.
</p>

<p>
To continue, <a href="nextpage.php?<?php echo strip_tags(SID); ?>">click
here</a>.
</p>