Once you've created your Cindr site, you're going to want to start telling people about it. Once you publish your site you will be able to share it across some of the most popular social networks by clicking on one of the social network icons shown once you "Publish" your site.
If you want your users to share your site, then add a sharing Bloc to your site, or add a Bloc with a Facebook share button (such as a contact Bloc).
You can also set an image for your site that will be shared. Learn how here.