In that case, visiting a smaller casino on weekdays would be a better choice. Mondays through Thursdays typically attract fewer visitors, leaving you to enjoy your favorite games in peace, with fewer people competing for machines and tables.
It's widely accepted among players that the optimal times to play slots are early morning or evening, with peak hours typically occurring between 8 pm and 2 am. Take some time to watch the particular machine to gauge when it is most likely to pay out.