This week, learn how to install an Omeka plugin. Earlier on the blog we talked about using Sitenotes, and this tutorial shows you how to install that plugin.
The installation process is the same for all plugins, but be sure to read the instructions (found next to each plugin on the http://omeka.org/download/plugins/ page), since configuring each one is slightly different. These instructions also provide some coding assistance to help make the plugins work with your public themes when necessary.
So, go forth, and install some plugins.