I used to wait for things to go on sale..but that has left me without appropriate clothing for the season (still working on re-vamping/replacing a whole wardrobe). What's been happening the past couple of years is that the weather changes, and I'm scrambling for clothes - and I end up buying in a bit of a panic, making mistakes in the process.
New approach: If I see something foundational/basic on sale for winter (right now I mean), I'm going to buy it, but I am not going to buy end-of-season sale stuff in the hopes that I'll like it, that it'll fit etc. *next* winter. Further, I'm starting my spring/summer shopping as early as possible. In addition, I will likely buy more at the NAS next summer, so I am not left floundering when fall/winter rolls around.