Arcee,
JFBConnect can automatically include the social buttons in Joomla and K2 content, and a few other extensions that can work with Content Plugins. I believe MyBlog has a option to enable content plugins, but I could be wrong.
If it doesn't, then you'll need to manually add the social widgets either using a module that shows up on your MyBlog menu items or by adding the {JFBCLike}, {SCGooglePlusOne}, etc tags into the MyBlog template files. If you need help doing that, we can give general instructions, but we don't know the MyBlog component well enough to have specific instructions on what file(s) would need to be modified.
Hope that helps explain and get you started,
Alex