I have been looking at corresponding squares recently.
It can be pretty hard to visually calculate and imagine them in your mind.
What I was wondering, would you ever be allowed to draw your plans on paper? I know in tournaments you are allowed pen & paper for your moves, could you scribble on that or under what circumstances would this not be allowed? I would have assumed in world championships you would not be allowed to do this. Is my assumption correct and what about club level / school players etc?
Example of what I mean by calculation: