I have been making my laundry soap for just over 4 years. What a savings. I make a 5 gallon bucket which turns into 10 gallons after all is said and done. I use to use Fels-Naptha bar soap but after a lot of research I have switched this time to Kirks Castile since it is more natural and am very happy in how this soap does not thicken as much so there are no chunks to shake up between each use. The girls love helping me make our soap. Start with shredding the bar of soap of your choice (Ivory, Fels-Naptha, Castile) I have a old cheese shredded I keep just for this purpose. Then you melt the soap in 4 cups of water on the stove. You fill a 5 gallon bucket of HOT water half way then add the melted soap to the bucket. Mix well. Add 1/2 c of Borax and 1/2 cup of Washing Soda and mix until all of it is dissolved.Then you fill the bucket to the top with more HOT water. You let sit over night with lid on it and the fill smaller container of choice with lid ( I use an old laundry soap container I recycled from a friend) half way with mixture and other half with more HOT water and shake up. Now you are ready to use just like any other laundry soap. I do like having the old laundry soap container so you can measure it in the cup the same way as store bought. You will need to shake up between uses in case the soap "gels" The Fels-Naptha did but does not seem like the Castile has done that yet. I enjoy the natural fresh smell from the Castile. You can also add 10-20 drops of essential oils in your bucket which I have not done yet. We will try that with our next batch.