Here's my latest video about Luminar, demonstrating how to use the Color Balance filter.
I use this filter a lot. It allows you to quickly and easily change color tones in a photo. There are three color sliders and then three drop-down selections for tones (Shadows, Midtones, Highlights). You simply choose which section of the tones you want to adjust, and then slide the color sliders accordingly.
In any given photo, I may adjust only one section of tones or I might adjust all three. It just depends on the photo and the outcome of my experiments with it. I feel like that is what a lot of this comes down to: experimentation. There is no formula for using this filter. Just move things around until they are pleasing to your eye. It's very simply yet powerful.
Take a look at the video and let me know if you have any questions!