Don’t recall. Let go of what has passed.
Don’t imagine. Let go of what may come.
Don’t think. Let go of what is happening now.
Don’t examine. Don’t try to figure anything out.
Don’t control. Don’t try to make anything happen.
Rest. Relax, right now, and rest.
These are a modern take on the 'six nails' of a 16th c. Indian sage named Tilopa.
Reading them, I'm impressed that the UNSG, as well as all the other participants, should take them to heart before their jaw-breaking begins