What ever you do do not use this recipe for a do it yourself carpet cleaner. I would have to say this is one of those throw everything at it and the kitchen sink mixtures. In Sarah's recipe she uses two different types of bleach along with two powerful soaps, and one fabric softener that does not add to the cleaning ability of do it yourself carpet cleaner. Not only is this carpet cleaner likely to bleach your carpet it will leave dirt attracting residues that are likely create a bigger spot than the one you removed.
I have been cleaning carpets in Tampa FL for over 5 years and I have seen a lot of home remedies that will not only take out a carpet spot but also take out the carpet color. Today's carpets are pretty tough but they are not impervious to damage. I have seen my fair share of damaged carpet. Most of the time it's because someone decided to try a little bleach in water to remove a spot or stain. Bleached carpet is the second most common type of carpet damage I come across in Tampa FL. The most common cause of damaged carpet is pet urine deposits.
If your going to make a do it yourself carpet cleaner stay away from bleaches and too much soap. A few drops of dish washing detergent in 3 cups of water will take out most carpet spots in your home. Make sure to rinse them really well and dry them with multiple towels. Promise me you will not make this evil do it yourself carpet cleaner.