Just tell them to come to the gym and hope they show up. We'll nickel-and-dime them later.
As far as your poor old dad is concerned, same thing. Just get his ass in the gym a couple of days a week, show him the basic lifts, make sure he gets stronger, and then worry about the exotic shit later. You should like the kind of micromanager that will scare him off anyway. For now, squats are all the "metcon" he needs, and cleaning the gooey shit out of his diet will work better than all the training he can do to drop him down to a better body composition. Put ye not cart before horse.