Brown Sunglasses

EDM Challenge #11  Draw your glasses or sunglasses.  I feel very strongly about brown lenses in sunglasses.  They make the world look even more amazing, especially clouds.  When I drive with brown lens sunglasses, I am constantly gazing at the clouds.  They make everything look like a Maxfield Parrish painting, and I love it.

I do not know how to draw shadows.  I wanted to add them because otherwise it just looked like the glasses were floating in space, but I don't know how to make it look like they're on a surface, especially when it's a plain white surface, like this one.  Something to practice, I think!