Here it is! Now that I know how to do this, I want to show you how!
You need to download a photo editor. I recommend Photoscape because its free;)
You start with a canvas. Go to batch editor and click add and add spaces. I would make it about 128 pixels. Then hit edit. Design it the way you want and save it to your computer. Go here and copy the code in the box. Go to your blog design page and hit add a gadget. Go to the HTLM Java Script. Paste your code in the box. Set up a photobucket, which is free, upload your button, and then copy the HTLM code. Return to your add a gadget and fill in where it says YOURBUTTONLOCATION with the HTLM code. Then fill in YOURBLOGADDRESS with your blog URL. Be sure to put everything right and it should work. If you have any trouble or if this is confusing, leave me a comment and let me know=)
Enjoy your button!