To complete a ¾ back swing from here should I be just cocking my wrists so as to limit too much shoulder turn?
Firstly i think its important to define what people think is ‘cocking the wrists’ or ‘hinging the wrists’.
From this image if i decreased this red angle (ie make the clubhead go up away from the ground) this is what people tend to actively do in their swing. The combination of turning the chest and cocking the wrists are two separate actions that can be achieved on the takeaway BUT you CANNOT make these two moves at speed on the way in. Many golfers turn and hinge but it makes for a more complicated swing, especially at impact.
So to start the swing, the wrists and forearms rotate the club away without the upper body making any conscious turning or shifting. If you imagine hitting a tennis shot 3 or 4 yards, the action would only come from the racket, wrists and forearms. only when the shot gets bigger will the rest of the body start to get pulled and moved.
In this image you can see how the red angle has not changed, just rotated.