Bloggers are writers. Even if you're into photography, video making or sketching and drawing.. and are blogging about those skills, you need to write well.
After completing your post, read it with a fresh eye from the perspective of a reader to check if you enjoy it or if it needs changes.
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.