I just finished up a first release of my first ever roguelike game called "Robot Zombie Ninja Wizard". In this game, you take on the role of a robot, zombie, ninja or wizard, each with their own spells which can be used to traverse and conquer a randomly-generated dungeon. The game gives the player quite a bit of freedom to build their character in different ways, and has a decent selection of equipment and items to find along the way as well as enemies to fight.
The JAR file for running the game can be found here: https://github.com/bprollinson/robotzombieninjawizard
It should be runnable on Java 1.8 or Java 1.9. I'm simply looking for people to try the game out and give feedback. In general, what is a good process for finding beta testers for a game?