I always 'balled' socks like others on the thread but then decided they look better, go in the drawers better, if they are flat. Pair the socks, fold in 3, fingers in top third of one to fold it out and over the rest. Voilà, nice flat socks, known as steamrollered socks in my family. (DH seems to own hundreds of pairs).
I think the shirt ironing order of collars and yoke first originated with flat irons when you started with the double fabric bits when the iron was hottest. I do it that way because my mum made me, and never thought to change
I do like a tidy airing cupboard, so keep all folds to the back like Anthea