December to February is the best. Not as crowded. It’s not as hot either.
Download the app and watch the wait times. If Pooh or pirates have more than a 40 minute wait the park is too busy! Haha I have a calendar that shows from previous year on when busiest and slowest times are, though I’m sure you can google it too!
Mid January - February is the least crowded time generally speaking. Late August - early September is another good time. Any month that is out of peak season is great.