I don't have them available to post, but I printed out pictures of my sump and labeled them with a key, both on the picture and where I could physically with a piece of tape. I then use those with a checklist and written instructions for each checklist entry. I agree with Sleepydoc above - minimialize the routine as much as possible. I also think as much detail as possible is a must as well as reassuring your sitter it's OK to contact you whenever. I have a small fish room so I usually put one of our wireless Arlo cameras in there so if there is an issue the sitter can visually show me what's happening.
Some examples from one of my written lists I left with my teenage daughter. Yes, I agree it is like writting instructions for a board game, but the more detailed you are the less liklely they'll be a misunderstanding. I've had a professional take care of the tanks as well - he was given the same level of instruction whether he needed it or not.
Filling the auto top off for display tank:
1. Use the valve labeled "A" and turn to open
2. Fill the auto top off tank until it reaches the marked line
3. Turn off valve "A".
4. Important: Do not leave while the tank fills or it can flood the room!
Filling the Clownfish and Goby tanks with fresh water:
1. Use the freshwater hose with valve marked Valve "B" to fill the 1 gal white container. Be careful to turn off the valve before the jug fills, then wait as the water finishes draining out the hose.
2. Gently poor the water into the tank until the water level is even with the bottom of the rim.
Check skimmer:
1. If the skimmer bowl fills up to ¾ you have to empty it. You do not have to clean the insides; just empty the dirty water.
2. Make sure one side of the kitchen sink is empty and run the water.
3. Turn off the switch labeled "Skimmer" on the electrical panel.
4. Make sure you see that the bubbles have stopped.
5. Grab the bowl with two hands and gently rock back and forth to separate it.
6. Take it to the sink, remove the lid, and empty it into the sink. Do NOT rinse!
7. Push the bowl back on the skimmer gently until it seats. Put the lid back on.
8. Turn the "Skimmer" switch back on and make sure it is bubbling. DON"T FORGET THIS