trying to add stumbleupon badge

I’m trying to add a StumbleUpon badge so that someone who reads a blog post on my site can easily click and share, just like they can easily share on Facebook or Twitter (no one ever does, but that’s a different issue altogether).

Ideally, I would like to add StumbleUpon to my “Share” icon that appears directly underneath the end of the article. The thing with what looks not quite like a human eye as the logo. Someone clicks on that, and they can choose Facebook, Twitter, Google Plus, etc. I’d like to add StumbleUpon, but to be honest I don’t even remember where this Share feature even came from. It doesn’t show up under any of the plugins I have and I don’t remember if I got it off another website. I honest to God can’t find it in my Appearance–>Widgets tab, and don’t even ask me to go into the actual code.

Yeah, it’s kinda scary that I operate this website all on my own.

Alternatively, I am perfectly fine placing a StumbleUpon badge on the right sidebar. I know HOW to do it as I’ve watched a tutorial on Youtube, except it doesn’t work for me. I’ll move the text sidebar and insert the StumbleUpon badge’s code provided by the actual StumbleUpon website (with the code beginning and ending in the <> icons, I know). But on my actual site, while the blank white space for the text shows up, no StumbleUpon badge does. Nothing at all shows up. It’s not even like the naked code is there; it’s literally just an extra blank space.

So in short, I’m trying to figure out how to add a StumbleUpon badge so that people could more easily share it. Any help would be appreciated.

Sincerely,
ARB–Angry Retail Banker
http://www.angryretailbanker.com