At the writing of this tutorial I was upgrading from version 2055 to the latest version 7249.

The simplest way to upgrade is to use the subversion command:

svn update -r {revision} {path}

This merges all of your changes with the new version.

Manual Upgrade

Due to having a very old version, manual upgrade was the only option. To do this I carried out the following:

1. Take a copy of the live site over to a development version. I would suggest having a copy of include/config.php on your desktop.

2. Download the latest version to a temp dir on the dev server

3. Overwrite the current files on the dev server with the new version