What is the best way to prep a car for outdoor storage for the summer in Florida?
If you are on the seaside, keep the salt off it by putting a light covering on it; open ate the bottom to allow air circulation. If extended time, take the battery out. Make sure the oil in the engine is fresh, the tires are up to normal pressure, and cover up openings such as exhaust pipe & air intake. The best place to store it would be in a garage or carport if available.
If it’s more than 2 or 3 months, you might want to put it on jack stands, too. That will prevent flat spots on the tires.
How long are you planning to store it? It makes a difference.
Consider removing the battery to protect the battery and make it more difficult to steal. If more than a few months (maybe less since it likely will be hot) then a fuel stabilizer would be good. Out of the sun would be good. Protected from the elements and animals is another thought. If it is going for more than a month, consider contacting your insurance company, you often can temporarily cancel the insurance other than comprehensive so you are not paying for that expensive collusion.
While putting it on jack stands should not hurt, it really is not necessary with modern tyres.
Resist the idea of having someone drive it. Short drives are hard on a car it likely will be better off without being driven and you can’t cancel the insurance if it is going to be driven and certainly you don’t want someone to just start it and let it idle.
Put it where a tree won’t fall on it when the hurricane comes!
Even if you use a car cover, you will still need reflective sun shades for the windshield and the rear window. Most car covers let in a lot of light. You should also take other steps to cover the tires all the way to the ground to protect them from the sun. If you will be storing ot for a long time, get some fuel stabilizer.