The basics of caring for a scorpion in captivity is A, knowing where the animal originates from. What type of a scorpion do you have in your possession? What is his natural habitat like? Is he a desert scorpion? He's got to be set up in the appropriate location in your tank. He's got to be in a desert environment.
If he's a tropical scorpion, just the opposite. He needs more of a humidity chamber. He needs to go under the ground where he can stay humid as much as possible.
There's temperature considerations. There's humidity considerations. Safety considerations in terms of letting him have a burrow by having deep enough substrate or a significant hide spot, a piece of cork or a hide box in order for him to get underneath.
So it's a fairly simple setup for a scorpion. Many of them, like this Emperor we have here, are nocturnal predators. So you might want to put a light on top of your tank that you can view the animal. A red light allows you to see him and he can't really see anything on the tank itself. A red light is an infrared light and they don't see. Ditto with a black light. A black light will illuminate the animal so you can watch him forage for food but he's still pretty much in the dark.
So setting up a scorpion, straight forward event. Do your homework. What do you have? Get the right size tank for him. Ten gallon tank is usually plenty for most scorpions. Substrate, heating, lighting, hide spots, all differ based on where it comes from. But very straight forward and simple to do. Scorpions are easy animals to keep. Low maintenance items. That's why they're so popular.