Adding a plugin is a lot like adding text. To add a plugin to a page, first go to list and click the 'create new content element' icon:
From there, we need to choose what kind of element. Since we are doing a plugin, click on the 'General Plugin' option:
Finally you should choose where it goes. Generally this is just "Normal"
Once you have your plugin layout, it will look a little bit like the content element layout. To choose the Type of plugin you want, click the "Plugin" tab:
Then, click on the drop down list and choose the plugin you want: you should have been told what you are looking for. In this example, I've highlighted the "CableCar" plugin:
There may be additional steps to perform, but in general this should be all you need to do.