You don’t need to drink a ton of water right before a morning class if you’ve properly hydrated the day before; it won’t even really help. Just make sure to drink lots of water in the two hours following class and throughout the rest of the day.
One of my teachers always says, “You can come to class exhausted, dehydrated, sore, on an awful day, and you can make it through if you just breathe.” Of course it’s not ideal to be in that situation, but not every day is ideal. Just breathe! ?