Perfect rows of lettuce

I don't necessarily buy into the whole astrological sign thing but I am a Virgo and I do happen to like most things "just so" I'm also a fanatic about things being straight and even. I know, I need to relax and undoubtedly having 3 kids is bound to cure me at some point :) When it comes to gardening though, I admire full, lush, out of rhyme & reason gardens but I do love the look of perfect rows of lettuce and I find it easy to care for the lettuce this way. My method of planting lettuce seeds has always been using a straight piece of wood to mark where I dig. This year though I am trying a technique I saw online using flour to mark the rows. I unfortunately can't remember the site where I saw this but thought is was a great idea. We'll see how it goes!