There's always a million ways to skin a cat. We try to mow east to west directions. Sun playing off the grass will help pronounce the stripes. We don't use stripe kits, but run our baffles wide open mid or high lift blades and I'll get upset if i find a deck set below 4"s. All our decks are level as we'll, no pitch or toe or any strange i heard from that guy tricks. Deck design, mower speed, blade selection, cutting height, turf type, direction of cut, can all play a role in how pronounced your stripes are.
Lawnmowerfanatic, can stripe with a push mower better then anyone I've ever seen. But i think he just played with it enough and is skilled with his push mowers enough to get nice stripes.
Just try some different cutting heights and directions until you get it.