More volume in your hair will make your face appear smaller than it is, and volume is often achieved through the use of hair products. If you use a high quality product, you'll get high quality results. So make sure you're using good shampoos, crèmes and pomades, so your face-slimming haircut will hang in there as long as you want it to. And remember -- high quality doesn't necessarily mean super-expensive. Shop around and check fashion magazines to find out which products give you the most bang for your buck.