I've told him/her before how do it so he'll remember. You will just cause yourelf and your child more stress.
Yes, we may have explained something to them before and maybe even explained it 3 or 4 times, but really, they don't remember.
For them to remember something it has to be repeated over and over until it makes itself into their long term memory. It needs to become "routine."
My son loves to drive the tractor and loves to plow the garden working the soil and getting it ready to plant. So of course my husband has explained to him how to drive, how to move the controls, and how to lower the blades and since my husbands remembers that he has explained all that to him and that he doesn't have to again, he and our son have so much more stress. My husband is yelling at him to change gears, slow down, don't do that, do this and our son is stressed out because he is being yelled at.
If on the other hand each time our son is going to use the tractor in the garden my husband needs to go over with him all the guidlines again, helping to plant (no pun intended) this into his long term memory.
All kids with autism may not be like my son. He doesn't have much of a shorterm memory so anything new has to be repeated several times before it makes it to his long term memory.
Never assume our children remember what to do because we've told them how 2 weeks ago.
Which brings to mind a topic for another post.....
From my world to yours......