NOTE: always take a database backup before upgrading!
If you have compiled Nurpawiki from source, you need to get the new source and compile it.
If you're using a packaged Nurpawiki, just install the latest package.
Configuration files may require changes from time to time. See e.g., SiteConfiguration for notes.
The nurpawiki database will be automatically upgraded when you try to access any of your Nurpawiki pages with your browser. You're strongly recommended to backup your database before attempting an upgrade.
Note that it is impossible to go back to an earlier version of your database once you have upgraded to a later version.