The model already has a roundish face, this style just makes her look like a football - a bald football.
.. I also suggested that Turkish hijab styles were the best for round faces as they make them appear longer and thinner if worn correctly, ie. covering the sides of the cheeks but leaving the chin and forehead free (the 1st picture illustrates the importance of the forehead when it comes to finding the right style for your face shape - not sure those two have got it right though..)
You can bring the 'shayla' as forward or back as you like; if you notice with the model below, had she brought it forward to sit across part of her cheeks, her face would have appeared longer. If she had taken it further back on the head, to reveal her cheeks, her face would have appeared rounder:
You can also use this concept to create the same style with scarves that you already have in your wardrobe:
Hope this helps!