just swing harder, just kidding. I was a framer for several years and know the motion of swinging a hammer quite well. One of my past bosses required us to hand drive everything except for sheathing, floor and roof decking. while working for him i felt like john henry. Although, you should be able to start and set the nail with 2 or 3 swings. 22oz was the largest hammer I ever carried but really liked a long handled (wooden)20oz framing hammer. I always felt that the heavier hammers were great if all you did was frame walls on the ground, but swinging it at or above head level was way more work than necessary.
good luck finding your perfect hammer