I have HomeBrew and Gradle already installed but can't figure out how to get Llanfair installed. If there's a video or step-by-step instructions somewhere I couldn't find it.

First of all, you download the files from their Github page (the dmg). After that, you execute that.

I even got you the page https://github.com/gered/Llanfair/releases/tag/1.5.4

PogChamp

Thanks! Got it working now.