Add a custom element in your ui-lovelace.yaml

I’m trying to upload this card → GitHub - usernein/tv-card: 📺 TV Remote Card (with touchpad and haptic feedback)

However, I don’t know how to do Step 2.

How to do it?

I currently have it installed with HACS and added to resources. However, it doesn’t work.

On a first glance, sounds like a cache/ressources problem. Reload the ressources via the three-dot-menu in the upper right in any dashboard. After that clear your browser cache.