Well i do have some tips
Whenever doing shading, if you want a pure look use a warmer color but if you want evilish look use a darker color
When lighting, always remember the position of the light so it looks collected
When it comes to styling, it is ok to use references but do not just copy, or atleast credit the original artist or photographer
When it comes to proportions, make sure the eyes are exactly one eye apart
And remember to have confidence in your art, even if you cringe at old stuff now that means you improved.
hope this helps!