Less is more, consider the flow of the room and what furniture and people tend to do in the room. Use a simple background and/or muted/lowkey details for most of it.

Highlight a few cool interesting things up front, using otherwise empty spaces that need it. Think more like wallpaper that coordinates with the whole room, and less like a wall of comics that just uses up the entire wall space.

I hope that makes sense. I watch a lot of dumb home renovation type shows with my spouse, and this mural thing comes up on occasion. That’s my only qualification.