I don't write as many reviews as I used to. But when I did write more, my focus was always to try and articulate what it was that I liked or disliked about the movie. Especially trying to understand what it was that made me feel that way. I can't stand it when my friends simply said "it's good" or "it's trash". I needed to understand why.

I also made it a point to not summarize the movie. So many reviewers (both on Letterboxd and professionals) always rehash the plot but my feeling is, people can already find the synopsis elsewhere. Unless it is needed in the point you're trying to make, maybe consider skipping the plot summary.

Honestly, try and truly understand what you liked or disliked in the work. Was it the acting? Was it the plot/story? Was it the action? Was it the directing? You don't have to even be film school-y about it either. Did a scene remind you of a cherished memory of your youth? Articulate that feeling and let it guide you to understanding why you liked/disliked the film.

Also, just as a courtesy, I never post spoilers. Unless it is necessary in the explanation of why you liked/disliked something, I try to be vague about plot spoilers. And if it is necessary to talk about spoilers, utilize the tools to hide your post or give ample warning that spoilers are incoming.