This table, borrowed from Catherine Failor's Making Natural Liquid Soaps gives you a quick reference for how to dilute your soaps.
Liquid soaps with high amounts of coconut or hard oils in them can be diluted in as much as a 40% solution. Soaps high in soft oils, like olive or sunflower, will start to congeal at as low as 25%. Most mixed recipes will do best somewhere in between 25% and 35%. Start with the higher dilution and then add more water if it starts to congeal or form a crust at the top of the bottle. Go slow, a little bit at a time, you can always add more water later. Taking it out is much harder!
Diluting Liquid Soap
| % Actual Soap | Water Added per Lb. of Paste |
| 15% | 48 oz. |
| 20% | 32 oz. |
| 25% | 22 oz. |
| 30% | 16 oz. |
| 35% | 12 oz. |
| 40% | 9 oz. |

