How to fix it: Even using the best preventive measures, sweat stains are bound to happen to the best of us. Thankfully, getting rid of them is not very difficult at all. For those looking for the cheapest, easiest option, the age old home remedy of combining 1 tablespoon of white vinegar with 1/2 cup of water and soaking for a half hour before laundering works well. Another, even easier option is good ol' OxiClean. Fill a container with hot water, add a scoop of OxiClean and swirl your garment around in the water until the powder dissolves, letting it soak for about 15 minutes. Rub the garment together at the source of the stains to work the solution in, and then launder as usual. OxiClean is basically the equivalent of combing vinegar, baking soda, salt and hydrogen peroxide, another home remedy, but without the science kit required to combine all of these things that many of us may or may not have laying around the house.
If all else fails and the shirts are beyond saving, it's time to throw out those gross, yellow stained undershirts and buy a new pack (which apparently got really expensive which is one of the reasons we're giving this tutorial to help prolong the life of your undershirts). If you happen to have stains on your dress shirts the above solutions should work just well, but can easily be prevented by wearing an undershirt (preferably V-neck) under your button down.