Scarlet, I keep a mental list of what I need that I try to remember while shopping but these days mostly I go "oooh I like that!" While I was building my wardrobe initially (for, like, 2 years) I kept a written list with me all the time and stuck to it pretty rigidly. Since I have my core more or less in place now (even though it needs to be upgraded), I find purchasing one or two items a month helps me update without having to spend a lot of $$ all at once. I'm not usually actively seeking these upgrades, but if I see a really great upgrade that I love I go for it; this is really helping me not settle, nor get too overwhelmed though it's certainly making it go slower