Rule 1. (Kill Expectation)
Go into the film without having read or watched anything. Trailers are acceptable, as they are sometimes created by film directors themselves, though even that sometimes is questionable.
Rule 2. (Kill Projection)
Assess what the film is trying to say or achieve within the realm of what kind of movie it is trying to be. Do not project your own expectations. Let the film dictate the level of expectation, be that tonally, narratively or conceptually.
Then, assess how well you think the film reaches whatever goals it set out to achieve.
Rule 3. (Kill Hype)
Don’t talk about the film with anyone who has not seen it, except if you’re encouraging them to go see it. Only discuss the film with those that have seen it, and discuss it hard. That’s what it’s there for.