My jersey lays so flat against my head that it takes away any shape my face had. I look like a smooth egg in every single style. How do you add some volume or shape?
The egg look is almost always a too-flat crown. Add a tiny bit of height at the top with a small claw clip or a little volumising scrunchie under the cap (not a big camel hump, just a soft lift). Instantly gives your head shape and frames the face. Step by step here: how to stop the egg look.
Let the front sit a little further back off your forehead instead of pulling it right down to your brows. That alone gave me a face again.
A slightly structured fabric like a light crepe or georgette holds shape better than flat jersey. Jersey is comfy but it clings to everything.
Face shape matters too, some styles suit round faces, some suit long. This helped me pick: the right hijab for your face shape.