One thing I have learned from my post on turning a bar of soap into liquid hand soap is that some people prefer soap to have lots of foam. The homemade liquid hand soap doesn’t easily foam, and there is a good reason for this. According to a comment from Sabrina Sumsion:
The sudsing effect is actually added to all store bought cleansing beauty products. The reason is because of marketing. To convince women to stop making their own products and buy off the shelf, they spent a lot of money to sell the idea that suds are necessary to prove a cleanser is working. Since homemade products rarely produce suds (because it’s not necessary) they were portrayed as inferior. … The short answer is the suds come from added ingredients. Your bar may have a lower ratio of “sudsers” in the ingredients and when diluted further, the sudsing effect is basically negated.
Still, there’s nothing wrong with liking soap to lather. If that’s your ilk, try putting the liquid soap–homemade or not–in a liquid foam dispenser. These devices aerates the soap and makes it extra sudsy. Foaming dispensers start at about $5, but since they use less soap overall, they pay for themselves over time, which makes them a fairly frugal option for your house as well.