Keep in mind that this homemade soap is different from commercial detergents, which contain optical brighteners to make clothes appear whiter and brighter as well as surfactants that provides lots of bubbles and suds. On the other hand, this is soap, pure and simple, and doesn't contain any scents, colors or common skin irritants. For me, the choice for homemade is a no-brainer.
I grate 1/2 the bar of soap with a cheese grater. Some people use a food processor, but either way, it doesn't take long.
Pour one quart of water into a pot and add the soap shavings. Heat the water and stir until the soap dissolves.
Add 1/2 c. of borax and 1/2 c. of washing soda; stirring to dissolve.
The liquid thickens a bit as it cools and gets gel-like and a little gloppy, somewhat like egg-drop soup.
I shake the jug up before pouring and use 1/2 cup per load of laundry.
I don't have a high efficiency washer and don't know much about them, but I have read that since homemade detergent is low-sudsing, it is safe for HE washers. If you're a member of the fancy washer club, you might want to look into that yourself.