Well I did a bit of both with my filly.
I did all of her basic groundwork, walking out, long lining and eventually lunging.
I backed her and hacked her out and did basic schooling, circles, turns, halt- walk-trot transitions and introduced canter and pole work. Once we were able to do all of that she was turned away. Following summer I redid it all again and introduced asking for her to start going on the bit and did a little bit of jumping over natural obstacles.
That winter (rising 5) she went to a trainer for a bit of a polish and further education. Establishing good paces and outline in all gaits, starting lateral work ridden, jumping coloured obstacles etc.
Having dealt with monster tantrums when I got her home, If I had the time again I probably would have preferred to do the work myself and had twice weekly lessons with her instead of sending her away for 6 weeks.