I may cannot post painted minis every month, but sure I can offer some inspirations outside our miniature painting bubble (as you all have already posted the usual suspects):
Marco Bucci did some great videos on ambient light
Zoe Hong has a lot tutoials on color theory
Mural Joe has a very good video on how to use color theory
And if you want to go a bit into serious display painting (or anything else) James Guerney's Color And Light should be on you book shelf (and he has some good and funny videos too).