Try things on, even the ones you wouldn't probably wear, but like the idea of. My heuristic is, when in doubt, grab two of the same color and try them on. You never know what you'll fall in love with
Make sure it fits. Numbers will always be numbers, so don't pay attention if it's a size 00 or a size 4. Praise your curves. Work what's best for your body type, and let go of unflattering clothes.
Wait. Yes, I don't have patience either but I always wait for the sales to kick in and get the dress I tried on several weeks (or months) ago. If you see that your number is running low, grab it as soon as you can.
Pull & Bear
By the way, Sales are soon starting, so keep an eye on the shops! Happy shopping!