WHY?
Photos are useful for a lot, and it's easier to keep your own collection for references and ideas that fit your taste, rather than doom-scrolling through Pinterest™.
HOW?
As my photography teacher pointed out, the best camera you can use is the one you have close at hand.
WHAT, WHEN + WHERE?
Whenever something sticks out, blends in or otherwise looks neat.
MOOD
LIGHTING
TEXTURE
FORM
& ODDITIES
. . . and then combine them together to draw exactly what you mean to say!