Respond when someone likes or comments on your post. Visit their blog and send your comment love. Courtesy brings in more readers and friends.
Post Ideas: At times you will just run out of ideas for post not sure what to do. use google and apps like Evernote to note down all that ticks in your mind. Something will surely turn into a new post.
Series of articles - Create a series of articles on your blog if the subject you choose to talk about is an extensive one.