Avoiding Tulum crowds
 

I understand it is best to visit Tulum early in the morning. Is there a day of the week that tends to be less crowded?

Saturday may be less busy since it is a travel day for many people. Sundays admission is free for the local.
Get there when they open, it gets very crowded early. We got there right after 8am (opening time in the past) and there were already 2 tour buses in the parking lot.
It gets crowded early because it is fairly easy to get to (straight drive down Highway 307), Chichen Itza is a long drive and a full day commitment. Coba is a much better ruin IMO. But if you just want to see a ruin, Tulum will do.