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.
Make sure you are interacting with your readers! If you are not doing so, your are not blogging.
Tags: Use of relevant tags is important from the SEO perspective. It helps the search engine track your post based on the tags you use.