Typically in Egyptian tombs, around a doorway the writing faces (literally) the door, so on the left side you read right to left and on the right side you read left to right. I've also seen them written in columns to look like actual columns. I think it's best to think of hieroglyphs as an extension of art / drawing.

(I learned some hieroglyphs at school so this link takes me back! The school's textbook was Barbara Watterson - Introducing Egyptian Hieroglyphs.)