Most cookies can come out pretty hard after baking them in the oven but did you know, if you put your cooled-down cookies in a container or plastic bag with slices of bread, your cookies will most likely come out soft?
That's because the moisture from the bread will cause the cookies to become soft. Just make sure they're in a cool area so that it doesn't go bad and takes less time for cookies to go soft. (i.e. Refridgerator, but I don't recommend putting it in a freezer so that it doesn't freeze and become freezer burnt)
My mom taught me this and it's made cookies I've baked a lot better.