Pop
For me, it depends on where and how I want to use it. A thick mixture will set up pretty fast, whereas a wetter mixture takes longer. I use both kinds, pouring it tu run down sides of mountains, or applying with a putty knife. A very small amount of venegar will slow setting time considerably. It sets up pretty good, but stays workable longer and takes many hours to dry and cure. No hard and fast rule for mixing. Just add water until you get what you want.
Lynn