I can't wait until we can stylize our blogs, but in the meantime, we can add interest. I've seen several posts with the images, but not instructions necessarily on how to add them so I thought since I figured it out I could share.
For me, I was able to enter the image at the top of my blog text by right clicking in the blank space and then choosing "Inspect".
Then I was able to right click in the Top of the box that appeared at the right to edit as HTML and insert the following code. I chose the <div><br></div> space right above where my body started.
<img src="INSERTYOUROWNLINK" title="" alt="">
You might need to add the size of the image to the code above so it doesn't cover up your post. I inserted breaks so that it would work.
and then save the blog