I have two types of loads. One for bullseye/benchrest and one for general purpose shooting. With my GP loads, I just run them through the Dillon 550. They come out every bit as good as factory ammo, probably better.
When I load for max accuracy, I do lots of extra stuff that most hand loaders would consider anal. I weigh each bullet and cull out anything more than .1 grains off. I measure each powder charge down to .05 grains. I use brass that has been fired 3 times or less. Each flash hole is inspected for proper diameter. And on and on. In pistol ammo, I can usually get the max velocity spreads down to 10 fps. In rifle, 25 fps.
My "trick" is not wasting time on precise accuracy when loading practice/plinking ammo. Not all ammo needs to be perfect. My GP loads take about 15 minutes per box whereas my precision ammo can take two hours for a box. Over the years, I have tested all sorts of reloading techniques and found out what works and what doesn't. Precision accuracy boils down to two things: selecting the right powder and uniformity.
The best "trick" in the book is to use a chronograph when working up loads. Keeping max velocity spread to a minimum is paramount. Making sure your loads track with the book is important too. By testing different variables, you can determine what powder, crimp, bullets, primers, cases, etc, works best.