Write them down and put them next to the schedule. As part of the rules, list the results if they aren't followed and make sure the punishments happen. Use positive reinforement. Whenever the child does something right on their own, praise them. Children with ADHD spend most of the day hearing don'ts and stop that's.
Praise goes a long way.
Make sure they understand what you are telling them. Remember they have trouble focusing. If you give them a long list of instructions, they're more likely to fail. Don't set them up for failure. Make sure you have their attention and then focus on them with clear careful instructions.