Before you perform an update of Pagekit or an installed package, make sure you have a backup of your files and the database. That way you can always recover previous states of your installation in case something goes wrong.
The recommended way of updating Pagekit is through its admin panel. Open System > Update and click the Update button. To make sure that the update was successful, just open System > Info. If everything went smoothly, you should see the new version number under the System tab.
Extensions and themes can be updated from the System settings in the Pagekit admin panel. Navigate to System > Extensions to see your installed extensions or navigate to System > Themes to see the themes which are currently installed.
If an item has an update available, you will see a green Update button next to the item in the list. Simply click this button to install the update.
For extensions, you will find the Update button next to the extension name.
For themes, you will find the Update button in the bottom right corner below the theme thumbnail.