Clicking on the main icon bar icon will show you a the Main Window.
From this window you can display all the packages, just those of a particular type or search for a package.
Once you have a package you are interested in visible, just select it with the mouse and you can install/upgrade or remove it through the toolbar or the main windows menu.
Most packages contain a component (file, directory or application) that you can set the installation location for from the Configure Package Window, which is shown when you install, upgrade or remove a package. A default location, which is usually a subdirectory of the Apps directory on the drive with the !Boot application on it, is shown to speed up the installation process for users happy with the suggested disc layout.
After a component is installed you can easily see where it was put by looking in Info Window or the Components Window.
The information for the packages comes from lists held on the internet. New lists can be added to the lists used from the Sources Window available from the icon bar menu.
To update !PackMan with the latest information from these lists select the Update lists options from the Iconbar menu.