Even if you’re salting correctly, every now and then, it’s going to happen. You’re going to add too much and render the food unpleasant to eat, if not inedible. Regrettably, there’s no quick fix, but there are ways to avoid wasting food you’ve over-salted. Removing salt from food you’ve cooked, say, a soup, sauce, or stew, is impossible, but you can add to the dish.
If you have time and ingredients, the best solution is to make a second batch of whatever you’ve oversalted and combine the two. If this isn’t an option, adding big starchy ingredients— potatoes, rice, pasta, bread—that need a lot of salt for flavor and adding fats such as cream can dilute the salt concentration.