I have put into practice a procedure that has a visual sequence for each step of the loading process.
After I shoot, I wipe the bore and lay the dirty patch on the tray next to my place for the ball. I can look at the loading bench and see that the rifle is unloaded and I can look at the target. When I return, I measure the next load of powder and with a funnel in the muzzle, I pour the powder. The funnel remains in the muzzle. I take the soiled patch and it goes into the trash jar at the station. When I lubricate the patch, I pick up the ball and load. If I am called away, I will insert my sort starter in the muzzle. This shows me that there is powder and a patched ball in the barrel. When I am ready, I ram the ball to the breech. With the ball loaded at the bench I can see that I am ready to go to the firing line since there is no dirty patch by the balls and nothing is in the barrel. I will politely allow no further distraction until after the firearm is primed and the shot taken.
These steps also give me the opportunity to demonstrate the complete loading process without losing track of where I am in that process.