If I use once fired cases, I first sort them for neck or case wall thickness. Then I'll deprime (by hand) and uniform pockets and flash holes. Then I'll put a light chamfer on the necks (so they go into and out of the die nicely). Next, I'll clean and lube the neck and then neck size the case. Then sort for concentricity or "run out" on the sized neck (maybe not necessary if using a bushing die without the expander ball). Next, trim and chamfer again if needed or sort out extra long and extra short cases. Finally, I'll sort by weight (now that they are all the same exterior dimension due to being fired once and sorted well). I prime by hand and load.
If I am shooting a case that has been loaded more than once, it differs a little. I'll still deprime by hand, but then just brush the pockets clean. Next, lube and FL size the case (if determined necessary). Then tumble to remove lube and trim/chamfer (if necessary). Possibly sort for concentricity/run out on the necks, but sometimes the FL size process will throw alot of cases out of concentricity. Finally, prime and load.
I will neck size as often as I can. When the cases start getting hard to chamber or extract, then I'll FL size. These methods are due to standard press dies. Custom FL dies or arbor press dies or bushing style dies can let a guy get by with less "runout" sorting and then you could FL size every time if you wanted to. The custom dies or bushing dies won't stretch the case as much either. There are alot of different measurments that I make while handloading, but that's a long story.
I've seen alot of cases get stretched a good amount (.010") just by the sizeing process alone, especially FL sizing.........so as mentioned earlier; always size before trimming.
These are just my methods, they work very well for me although quite time consuming in the early stages of brass preperation and sorting.