To install the tools for usage with your own version of Autodesk Maya you can simply copy the the files PRA tools package's scripts folder towards the scripts folder of Autodesk Maya. After copying the required files restart Maya and you should be able to see a new menu item added in the Maya menu bar called PRA. (PRA Main Menu) This contains all the functionality you'll need from the start and can help you further with the process of its usage.
It's recommended to start the logging in procedure - first create an account if you have none yet - after installation, otherwise much of the layout saving, user-defined settings, and import/export features of the tools will not work accordingly. You'll need to be logged into a registered account for the usage of those features. To start this procedure click on the PRA menu item and click "Log in...", if a user is already logged in press the corresponding option box to switch users and start working on your own account.
If you want a quick start to trying out the default animation tools run the Python command: PRA_aniToolbox()