1. Back up your template.
2. Put this in the HEAD part of your template, in the style section, if you keep your template organized that way.
You can alter the colors etc. to fit your own blog. You'll probably also want to replace all the annoying html br marks and replace them with real breaks. When I put stuff into the text boxes I lose control of the break marks.
3. Put this also in the HEAD section, in the scripts section, if you organize that way. Otherwise you can just put Steps 2 and 3 in the same place.
Same advice about the break marks.
4. Put this part in your sidebar, then modify it per the directions embedded within.
You can duplicate the structure as many times as you want.