I highly recommend
Ashley Greene's e-book, Ultimate Guide to Liquid Soap. It's a little pricey but you can usually find a coupon on her FB group, especially around holidays, including Fourth of July. This e-book is full of fantastic information about:
1. Creating good LS recipes. These are often not the same as great bar soap recipes, because some soap calc values (hardness and longevity, for instance) are inapplicable to LS.
2. Making fully diluted LS in 30 minutes by using more water to start (your original question).
3. Eliminating myths that unnecessarily complicate your LS-making process. Boy, there is a lot of that type of info out there! This book will help you to skip unnecessary steps, while maintaining the crucial steps and ingredients that are scientifically necessary, or perhaps just beneficial for certain outcomes that you may, or may not, desire to achieve.
... and much more. Some of the things I learned from this e-book were not published by any free public sources, at least, not that I could find.