How do i add this to my hompage?

[Totally Lost]

How do i add this code to my index page?...where do i input it?.... >_<

 

My 'images' are in: catalog/images

 

 

<?php

/**
* Change the name of the image folder
*
* Images must be named Monday.gif, Tuesday.gif etc
*/

// Change to the location of the folder containing the images
$image_folder = "images/days";

// You do not need to edit below this line

$today = date('l');

if (file_exists($image_folder."/".$today.".gif")) {
 echo "<img src=\"$image_folder/".$today.".gif\">";
}
else {
 echo "No image was found for $today";
}

?>