I would recommend that you set up and maintain a Moodle server instance. Some folks do this locally on their workstations or laptops. Another way would be to install a LAMP virtual machine and maintain Moodle on that. Finally, a cheap cloud virtual private server (such as Rackspace, AWS, and a plethora of others) would do nicely, so that you don't have to mess around too much with your own computers and you can have your test Moodle sites available anywhere.
Personally, for me, I learn Moodle best by messing around with it, installing it, breaking it, failing, learning, etc. When I tinker I learn, and Moodle is fun application to tinker with in my opinion. It is really nice to have your own server or virtual machine to tinker with Moodle, where you never need to worry about breaking stuff and you can always start over. If you will be responsible for managing and administering Moodle from the backend server-side, I strongly recommend you begin by just trying to set up your own Moodle server.
Good luck!
Jamie