Not a military instructor (just a lowly civvi PPL instructor
) but I was taught to teach start at the front, 30 deg segments to the left until you can't turn your head any further. Back to the front and then the other way. Throughout, keep moving head (especially around canopy frames etc). For a turn, start at the outside of the turn (ie look left for a right turn) and sweep all the way across to the inside of the turn before turning. In a high wing, always dip the outside wing before commencing the turn. In all types, when out of the turn do the opposite sweep, lifting wings as necessary.
PS. Always clean the windscreen before flight
