Go to Wordpress admin area and click "Plugins" and then "Add New" menu item.
In the right panel (left top) you will see "Upload Plugin" button. Click the button.
Next click the "Choose file" button in right panel (center).
Select zip file of the "Pager Widget" plugin located on your hard drive and press "Open".
Click "Install Now" and the zip file will upload to your site.
Now click "Activate" button to activate the "Pager Widget" plugin.
We've tested following plugins published by: Paul Ryan, Programmer, Distance Course Design & Consulting (DCDC), College of Education, University of Hawai'i at Manoa