[plugin WP Facebook Open Graph] Facebook Meta

Hey guys,

I’m new to WordPress. I have the WP Facebook Open Graph protocol plugin installed. It works fine for when I post a link to one of my wordpress posts on facebook, but I’m trying to figure out how to get a picture of my wordpress homepage to show up when i post the url on facebook(e.g. a picture next to the url). I don’t know much about meta and coding, so if your able to help please explain it in beginners terms.