OH! I have to share this hint with you that I'm having great luck with. I'm not sure if it's a true "Heloise Hint" but it sounds like her.
If you get something on a white, cotton shirt, do this: Get a cotton ball and a bit of hydrogen peroxide. DAB it on the stained area - don't saturate it. Then, LEAVE IT ALONE. Over an hour or so, it'll fade the stained area.
I had a bit of beet juice on a cotton shirt - NO RED LEFT! Yesterday, a bit of coffee splashed on another shirt - TOTALLY WHITE NOW!
Of course, you'll want to do a test area on it before doing this on your absolute finest outfit! But, it's something that's helped me.
And, if you get oil (like salad dressing or something like that) on your clothes, grab some baby powder and sprinkle it on. It absorbs the oil and makes it easier to wash out. And, THAT one is a real "Heloise Hint"!