Just as you've listed it. On my personal rating's list, I sometimes do a .5 if I can't decide exactly how I feel about a movie, but since half points aren't a thing here, I round down.

I base the rating on both how much I enjoy the movie's plot and how well it's shot or if I like the actors. An intriguing but poorly shot movie can drag down my enjoyment while a boring movie with actors doing their best with what the script gave them can raise my enjoyment.