<script src='http://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js' type='text/javascript'/>
<script src='http://nirav07.110mb.com/jsnow.js' type='text/javascript'/>
<script type='text/javascript'>
$(function() {
$().jSnow();
});
</script>
Copy aja script diatas kemudian paste sebelum </head> gampang kan?