Well, certainly I only do this when I have full day available to stay home. And i don't eat that day during the process. Maybe some juice or fruit at the very end of the day.
With the ES, there is nothing to "Kick-In". It's just for relaxing the ducts, if that makes any difference at all with a coffee enema. Never noticed any difference at all with or with out it. After the coffee is expelled, I usually get a second smaller release within 30 minutes (so some of it worked it's way higher up), THEN I may follow with a plain water enema and/or SWF. The salt water rinses through anything that was lingering. i don't always get the same follow-up reaction. i drink a lot of water during the day - salt and plain. you can't help but to hold on to a lot of it.
My logic using the salt water was that if the liver released anything, it would be in the upper intestinal tract and the salt water would push it through quickly. but i have never seen anything more than the what was in the initial coffee/ water enema release.
you could do another ES later - but that's part of the trial and error that's might be right for you. i'm always tinkering.