There are many ways to share your blog. If I understood right, you want to learn about sharing.
You can go to the settings tab of your dashboard and select Sharing. Then you can connect your Facebook, Twitter, Yahoo, Linkedin, Tumblr accounts with your blog. When you publish a post, your accounts will automatically notify your followers& friends.
Other than social media, make sure that you use categories and tags in your posts. They make your posts easily reachable in the WordPress reader and also in Google search results.
You can use the Follow Blog widget. Place it on your blog and readers can add their e-mail adresses to the newsletter. A newsletter is automatically sent when a post is published.