Ubuntu 19.04 (Disco Dingo) Beta is available today! I do this so infrequently that I always have to look up how to do it, so for future reference I'm tossing my notes up here. Here is how to upgrade to an Ubuntu beta version.
1. Make sure your current version of Ubuntu is up to date.
This can be accomplished by opening a terminal (Ctrl + Alt + T) and running the following command:
sudo apt-get update sudo apt-get upgrade
2. Launch update manager
Next, launch update manager with the code below in the command box (Alt + F2). The -d option tells it to look for upgrade distributions:
Just click the "Upgrade" button and you're done!
FYI, this can also be accomplished in the terminal (as opposed to the command box) with the following:
sudo update-manager -d
That's it. Don't forget to re-enable third party sources after you've upgraded.