I've been making my own laundry soap off and on for about a year now. I've tried different recipes but they're virtually all the same (In my opinion). Not only have I saved tons of money since I'm not buying overpriced laundry detergent, but I like the fact that the homemade stuff doesn't have anything in it that's unnecessary. It's great for people with sensitive skin....dye free, fragrance free (unless you want to add your own).
Anyway, here is the recipe I use for Laundry Soap
One tip I might share with you (If you use the large container vs. jugs) is that after your detergent "gels" overnight (you'll understand once you read the recipe), break up the gel with a large spoon or whatever large utensil. Add a few pitchers of warm water and break it up with your hands and then a whisk. This just gives you a smoother soap with less lumps. Although if your soap has lumps it will still work just fine, it's just me being anal! No lumps = Everything is right in the world....Well, it's a good start anyway!