The way I have learned and done it is to have the FP always on the controls while the rotors are turning, preferably looking outside too. That way the NFP can do all other tasks, including applying the parking brake. Can be awkward sometimes but it is possible. I try to apply a similar rule in the cockpit when flying, one pair of eyes always outside. Even if there is an emergency, one person flies while the other handles the task inside. An emergency may kill you, a collision will, generally.