Click here to see the demo or just take a look around Directions
Step 1: From the Dashboard, navigate to Layout > Edit HTML (you don’t have to click on expand widgets template), and locate your body tag": <body>
Step 2: Add the following section code right after it and Save:
<script src='http://www.blogspotvision.info/bspotvision/scripts/snow.js' type='text/javascript'>