An easy exercise is to describe what you don’t want to happen.
Telling a child “don’t drop the glass” results in confusion. The child tries to process the information and finds it hard to translate it into an action it should do. Eventually, the glass falls.
Asking the brain to avoid something leads it to focus on the thing to be avoided.
It’s the easy way.
The hard way is to describe what’s to be done. May it be to tell the child to hold on to the glass or to define for yourself what you want to happen.
What are you building?