First of all I must write that I am talking of my own mind processes. I am writing because it may be useful to others.
Shading - I have an indigenous Shading technique.
Shadows - I have drawn Art on Shadows. It is a great way to render. I now have understood this part.
Perspective and shapes - I believe 1 to 1 ratio and 1 to 1.618 (golden ratio) and 1 to 0.618 ratio are inbuilt inside me. I am aiming to perfect my observation skills using this advantage that I have (so I believe) and render Perspective and Shapes on paper as Art. It is mainly an observation technique.
That leaves reflected light.
And IT images. Digitally enhanced images.
Reflected light - Practice needed.
IT images - I plan to use DaVinci app. And I have ordered a mobile stand from Amazon. It will arrive on Monday. ( I hope to perfect my IT images rendering).
My good wishes to you!!
I have drawn a padlock using my newly developed observation skills as written in my earlier paragraph on Perspective and shapes.