I have to treat all of my husband’s work clothes every time I wash them. I didn’t give a thought to how much soap I was adding to each load in doing so until I noticed the clothes were getting dingy and a little gummy. Now I fill the bottle as instructed below, spray the clothes and add whatever is left in the bottle to the wash load (don’t add any additional soap). That is it. Almost free effective stain remover.
Fill a 16 oz spray bottle 3/4 full with water. Measure out the amount of soap you would normally place in a load of clothes and add it to the spray bottle. Spray stains and add the rest of the spray to the washer. For heavy stains allow clothes to set an hour or two before placing in the washer. Since you are using the soap you would have placed in the washer anyway the only added cost is your time and a little bit of water.