And/or, when you saw a movie, while you were at the theater, you'd just try to memorize the show times of any films you might be interested in seeing next weekend. Or you'd rely on what others told you about when/where they saw a movie.
And if all that failed (or you didn't even try), sometimes you'd just show up at the movie theater around 7pm without having done any research at all and see whatever looked good based on movie posters, titles, and actors you recognized.