Well, without seeing the PHP code we can't really advise you that much.
But, check whether your PHP code has comments, and is properly laid out.
E.G.
Harder to read
Code:
<?php if($blah=="blah"){echo"bleh";}?>
Easier to read
Code:
<?php
// The IF function for blah
if($blah=="blah")
{
echo "bleh";
}
?>