Popular Topics: Stay updated with new topics or popular topics on other blogs you follow.
Content is the king - In the blogging world so diverse and big, you need to establish yourself with a distinction. the only road to it is good, original and valuable content. Be creative, different and surprise your readers once in a while.
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.