Setup is very easy! By default this script is disabled, in order to enable it simply choose All Images or Individual Images from the drop down, as shown below from inside the template configuration page.
All images will load every standard image on the page with lazy load. There is no extra configuration or extra code to add with this configuration, it will just happen automatically. Individual images would be used if you want only certain images to load with this script and not all of them. To do this simply add class="s5_lazyload" to the image like so:
<img class="s5_lazyload" src="http://www.yoursite.com/image.jpg"></img>
This script is compatible with Firefox3+, IE8+, Chrome14+, Safari5.05+, Opera 11.11+