We'll I'm not really "making" soap, but I am saving money. I recently made a whole jug of refill soap for my empty foam pump from Bath and Body Works. I do love the foam pump soap from there, but even with it on sale it still costs more than what I did.
I just took an empty water jug (nice and clean of course) and filled it with a few bottles of Dial Antibacterial Hand Soap and some water. After emptying each 9.375 oz. bottle into the water jug I would then fill up the empty Dial bottle with water and pour it in also. I did this twice with each bottle of soap. So it's 1 part soap and 2 parts water. I think I paid around $0.55 for each bottle or they may even have been free. I've seen it go on sale at Publix for $1 a couple of times now. I'll be buying more when that happens again.
(The size of the bottle I used isn't important. I'm just telling you what I used. I can't remember if the water jug I used was able to fit three bottles of soap with water or 4, but I have great confidence that you can figure that one out yourself.)
You do have to buy an initial bottle of foam pump soap for the bottle and the nifty little mechanism that makes it foam up. I just waited until Bath and Body Works had a sale and while I used that soap it was a special treat. I love all the B&BW yummy scents, but I do like the White Tea & Vitamin E that I used from Dial. It's not too flowery for my husband and it doesn't leave an overpowering scent on your hands either. You may eventually have to replace your foam pump bottle with a new one. I'm interested to see how long it will hold out.
I'm keeping the jug of soap under the bathroom sink. The soap I used was clear so I used permanent marker to mark ALL OVER the bottle. My kids are old enough now that I don't have to worry about them drinking it, but if yours are young you might want to keep it up higher. (I wouldn't put it past my kids to have bubble-making experiments with it though).
Do you have any money saving tips to share?