I cant stress these things enough. These are big DON'T's in the tarantula world. I will add more as they come to me, but use them as a reference so you know what NOT to do.
NEVER release a tarantula into the wild!
NEVER give your tarantula to just anyone!
NEVER allow your tarantula more than a few inches from the top of the tank to the substrate where its walking to prevent falls!
NEVER feed your tarantula live pray that is larger than it is!
NEVER just reach in and grab a tarantula! There are proper handling methods for arachnids and you can find all of them online. Id advise that you use them if you don't want to get bit.
NEVER use wood chips or sand for substrate!
NEVER handle a tarantula unless you are 100% comfortable with it. A fall from just a few inches can injure/kill a tarantula.
NEVER use a sponge inside of a water dish! Sponges house bacteria.
NEVER house more than one tarantula in a single enclosure. Tarantulas are territorial and will kill other tarantulas that they come in contact with unless its mating season.
NEVER use a heating pad or any other "artificial" heat source for a tarantula. Most species are perfectly fine with 70 to 85 degree temps.
NEVER leave uneaten food in an enclosure with a tarantula. This keeps risk of injury to a minimum, and keeps bacteria growth down.
NEVER expose a tarantula to natural sunlight. Tarantulas are naturally nocturnal and although they can be in the sun for short periods of time, leaving them in direct sunlight for more than a few minutes can be fatal.
NEVER blow on a tarantula. It simply stresses them out.
NEVER underestimate an arachnid. Some of them move at lightning quick speeds and will be up your sleeve before you see it happen.
NEVER house your tarantula in an enclosure that isn't "cat proof". I learned this from experience..cats are ninjas and tarantulas can fall victim to them very easily. Always keep them somewhere your cat cant get to them.