Adding image to Bytetips theme

I’m trying out the Bytetips theme and wondered if someone could explain to me how to add an image to the left side of the main header/blog title where the Bytetips logo originally appeared.

Do I just replace their current ‘http://” address with an address for the image I want to use? I’ve tried that but the picture doesn’t show up. Right now it’s a color in place of it. Is there another step I need to do?

My blog: http://whitenoiseinsanity.com/

Any help would be appreciated. Thank you.

(*waving to Musnake* if you’re around! You were such a huge help to me with my blog last week!)