Installing 4 switch box using old wiring as a power source 1 black 1red and 1 white wire with no ground. I know I need to pigtail off hot to each switch. Which is hot red or black and what do I do with the one I'm not pigtailing from?

Well, two things.
Red or black are potentially hot. Only you can tell this. Maybe one, maybe both. Maybe neither. Depends on where the cable originates.

Second, and more importantly, You CANNOT use this cable to feed new loads. You MUST have a ground for new circuits and loads. You cannot use an old feed with no ground.

Stan, If this is existing, can he reidentify the red as a ground with green tape?