You can stop there if you like, or you can add glycerine if you feel like it, and anything else that seems appropriate. For the first attempt, I added a very small amount of glycerine, because that was all I had, and a bit of shampoo, which turned it pink and scented it surprisingly strongly. This shower gel was rather drying on the skin, probably also due to the shampoo. That one went into a handwash bottle and a second batch attempted. This time I just added glycerine, but quite a lot of it (having bought some more in the meantime*) - probably about one fifth of the total quantity.
This soap-in-water is most peculiar stuff. After it's cooled it remains the consistency of water for some time. It's only about 24 hours later that it becomes a gel.
Yes, this picture is supposed to be this way round. I'm showing you the jelly-nature of the shower gel.
This one is much less drying, though I did get complaints of 'tackiness' on the skin. Maybe not quite so much glycerine next time.
*Glycerine is sold in Boots as budget cough medicine, at £1.69 for 200ml. It is also sold in supermarket home baking sections, from 65p for 38ml, which is twice the price and much more packaging.