How to remove some tough stains

Blood - If it's a fresh stain, rinse with cold water first, then pour plain old Hydrogen Peroxide on the stain, rinse in cold water (repeat until stain is removed), Then wash immediately in cold water. If it's an old stain, pour Hydrogen Peroxide directly on the stain, rinse in cold water and repeat until stain is removed. Wash in cold water right away.

Chewing gum - PEANUT BUTTER. I don't know what it does, but it will remove chewing gum from just about any fibrous material. It will also get it out of hair too. You can apply it with your fingers or small brush (like an old toothbrush).

Ink - Pour either clear rubbing alcohol or Acetone-based fingernail polish remover (DO NOT MIX ANY CHEMICALS TOGETHER AS THIS COULD BE DANGEROUS) directly on the stain, rinse in cold water (repeat as needed until stain is removed) then wash in cold water right away. You can also use a hairspray with a high alcohol content instead, but Be sure not to let the hairspray dry on the garment because it can create a new stain.

Mildew - On clothing, you can soak the garment in a 1:1 solution of hydrogen peroxide & water (1 cup hydrogen peroxide and 1 cup water) rinse in cold water and repeat until the stain is removed. If the stain remains, sponge Hydrogen Peroxide directly onto the stains, then rinse in cold water and repeat. Wash the garment in warmest water that is suitable for it. Dry garment outside in the sun or in the dryer on the highest temperature suitable for the garment.

Permanent Marker - On clothing, use Acetone-based fingernail polish and rinse with cold water. (repeat until stain is removed) wash it in cold water immediately. On unpainted walls, appliances, etc. I use Acetone-based fingernail polish remover to get the most of it off and then a Magic Eraser to remove the rest. If it's on a painted wall, you can use acetone to remove the spot but it will remove the paint and the area will need to be repainted either way.

Above all, please use common sense. Do not mix any chemicals together because it can result in some pretty bad side effects, (chemicals burns, toxic gas, etc.). If you're sensitive to any type of product, be sure to wear protection. I have used all of these methods and they have worked well for me, but I cannot guarantee your results.