Some of the most common face shapes are round, square, heart, and oval. One of the key elements to remember when frame selecting based off of a patient's face shape, is more of that shape on their face creates more of that shape.
So, for instance, on a patient's face that is very round, similar to mine, round on top of round equals more round and what’s more appealing is introducing some angles, like a rectangular or geometric frame shape, so that it breaks out some of that roundness.
With the square, it’s the same. You don't want to put more square on top of a square-shaped face, you want to introduce curves or an oval.
On a heart-shaped face, you want to introduce any shape, but you do want to be conscientious in regards to anything that’s top heavy on the eyewear. Also, with a heart-shaped face you want to be conscientious of their cheekbones to make sure that those frames aren't sitting on top of them.
On an oval, pretty much any shape will work on an oval face shape. So, sky’s the limit. Try fun, funky shapes and oversized sizes on an oval.