Yeah, as Brook implies, that's a hard one. I seldom cook from recipes... because I rarely cook things that have to adhere to strict formulas, so I just have the routine of the procedure "down" and I just do it the same way every time. (On a super-easy-to-understand scale... a PB&J, or cheese n' crackers... Some might NEED a recipe to make a PB&J, but most of us do not, 'cause once you've made one a time or two, you're basically set for life, and don't have to open the cookbook anymore...)
Baking is different, because one really can't just start throwing hand-fulls of flour and sugar together and expect to have a good, consistent product result. My last few kitchen positions I worked a lot of night-baker positions. I proll'y have about 100 fairly detailed specific recipes in my head for bread, rolls, cookies/biscotti/brownies & bars, donuts/fritters/muffins/danish, biscuits, pie crust/cobbler-crust, fruit-crisp crumb-top, etc. Not because I'm GOD but because I had the MUNDANE chore of baking these items monotonously every single night for years!
Those items I only did once a week or less- I had them written down in a notebook that I kept in my work-station in the bakery at camp. Also kept them all in a file on the computer.
At home, when I try new recipes from a book or mag- sometimes I'll rip the page from the mag and carry at my hip in the kitchen... cookbooks, to avoid getting the pages messy in the kitchen, I usually hen-scratch them down an a yellow sticky-note and stick to the cupboard-door that I'm working in front of at the counter.
In other commercial kitchens I've cooked in, most restaurants, hotels, etc have masters of all recipes in a 3-ring binder and sometimes posted under protective plastic in all work-stations so all cooks have easy at-a-glance-access to them when in a hurry on busy nights... For instance, all restaurant menu item recipes were posted on the main cook's line, all salad dressings were posted on the wall behind the 50-gallon Hobart mixer, etc.
