Blog Guidebook: How To Place A Button In Your Sidebar
Buttons are cute little icons that are made to represent a blog...usually in a smaller pixel* format, like 150x150. A lot smaller than one's banner/header pixels.
So, if you love a blog or a product and want to show the world you care about that item or blog, then you'll want to copy and paste the code they offer beneath their button. If they don't have code posted, then all you have to do is right click the "picture" of the button and save it to your desktop as a .jpeg*. If code is available all you have to do is copy and paste. (BTW, you don't want the code to show when you add the button).
To read the complete tutorial click HERE