Type into the YT search bar what your video is about. YT will show you what people are searching for. Mix those keywords every which way you can, as long as it's relevant. Populate your t/t/d and cc with these keywords.
After some time, perhaps a week or two, go into Analytics and you can see the search terms that people are using to get to your channel. Make more videos for those search terms and their variations to build authority in that category.