1. Put your forum into the maintenance mode.
  2. Create a backup of files and DB of your forum.
  3. Download this archive, unpack it on your local PC and upload files from it into the same folder where your forum is.
  4. After you have finished uploading the files, point your browser to http://www.yourdomain.tld/forum/upgrade.php – where www.yourdomain.tld/forum is the URL of your forum. You should then see a page asking you for a few bits of information.
  5. From this point, the upgrader should walk you through everything. Please remember to delete upgrade.php after finishing the installation. If you do not delete it, it is possible that someone could compromise the security of your forum with it.