So let's talk about salt. From kosher, iodized, sea, pink and grey, there are so many varieties of salt to choose from these days. Kosher is my salt of choice to cook with. Kosher salt has a larger grain and a flaky appearance. It is named for its ability to make meats kosher, since the large, flat grains adhere well to meat to draw out liquids. Unlike iodized table salt, kosher salt is additive free and has a very clean taste. It is very important to understand what type of salt a recipe is using, since a tablespoon of small-grain iodized table salt is much "saltier" than a tablespoon of larger-grain kosher salt. I also prefer the hand feel of kosher salt - the larger grains allow me to feel the salt in between my fingers and pinch an appropriate quantity to use for seasoning my food. Recently, sea salts and the various colored gourmet salts have become popular. These salts are special - they tend to carry minerals that give the salt its color and impart an earthy flavor to the final dish. These are best used at the last minute to garnish or give a dish an extra pop of flavor.
It is important to season at each step of the cooking process, as this creates a gentle balance of flavor rather than an abrupt sharp saltiness that often occurs when all the seasoning is left until the end. If a recipe calls for one tablespoon of salt to be used, place the salt into a little bowl and season each component as you build the dish. In addition to its flavor impact, salting at each step may be necessary for proper cooking technique, as salt pulls liquids out of foods. Adding salt to vegetable sweats and sautees is essential for this reason, and salting meats right before searing helps ensure proper caramelization (doing it earlier can leave you with less-than-juicy steaks). And when making things like french fries, sprinkling them with a pinch of salt right after removing them from the oil or oven helps to develop crispness.
When cooking stews, soups or sauces, however, be wary of over-salting. Under-salt as you develop the dish, and understand that the soup, stew or sauce will reduce and the flavors will become more concentrated. Also, season lightly if the dish requires you to add salty things at the end (e.g., cheese in pasta sauce). You can always add a little bit of salt at the end to season things to your liking, but adding more liquid can be problematic if you are shooting for a particular texture and thickness. If you do find your dish over-salted, you can always try adding more vegetables, rice, pasta, or whatever to help soak up the excess seasoning.