Grid products for dummies – beginner plea

Hello,
I am relatively new to WordPress and not overly technical. I know a bit o html but no php. I am working with the `Simplify Extend’ theme and want to use the Gridproducts for some of my internal pages.
I have installed the plugin (v.1.2) and network activated.
Now what do I do?!!
Please can you let me have step by step instructions – for dummies style 🙂 I think it may be that I haven’t ventured into setting up product categories as yet as I have so far just been working on basic styling, setting up pages and navigation.
Many thanks!
Paula

http://wordpress.org/extend/plugins/grid-products/