1 cup washing soda--NOT baking soda and cannot be substituted for baking soda
1 cup borax
2 cups ground soap--I recommend Dr. Bronner's Castille Soap
and you can put 1/4 cup Oxi Clean in there too.
I just use my cheese grinder to grind the soap. You mix it all together in a big bowl and use 2 Tablespoons for a load of laundry. It doesn't seem like much because it isn't full of all the fillers that store brands have. Some people add essential oil for fragrance but we prefer no fragrance to help with any allergies.
Generally I use cold water to wash my clothes because I like to save the hot water expense for my scalding hot baths. For fabric softener, get a Downy ball and fill up to the line with White Vinegar. I promise your clothes will not smell like vinegar. I store mine in this canister which is much more chic than a box of Tide. I'm about to start experiments on homemade dishwasher detergent so if you've found one that works, let me know.
My original recipe came from www.modcottage.com.