If your winch
does not have safety
switches. One that stops when you remove your hand or foot from it.
Then you need to plan ahead on laying out the line you are using.
Ensuring that it is fairlead properly to the winch
That you can be at least an arm's lenght from the winch so you will have time to let go of the line.
No rings or other jewelry on your wrists or fingers, those will snag the line and pull you into the winch.
Playing out on the winch is hazardous, because the line is moving through your hands toward the winch. be sure that the line is faked out with no snares or tangles in it to distract you from what you are doing.
Discuss the procedures with anyone who is going aloft with you using a power winch. Do they have a safety
line in case of sudden slack off of the hoisting line. Can they be lowered by other means. Where do you stand and where when hoisting to put the tail of the hoist line, without tangling it. All of the above must be discussed and everyone understands the hazards of not following procedure or being distracted. And when lowering the person aloft, is it done under power or by surging the line around the winch.
And practice by raising that person a couple of feet above the deck
and lowering him back down so that all steps are well understood.