Thank you for your comment and sorry for the late reply. I still struggle a lot when it comes to choosing the 'right' colors. What i do is i look at a lot of referances (which mostly consist of paintings from my favorite artists) and try to understand what works and what doesnt. I pretty much steal the color palettes that look the most attractive. This is why i did the painting above with the girl standing before a blue/yellow wall. I wanted to experimence with those colors which i saw on some of Marc's paintings (mentioned above). As for the girl on the last post i originally wanted to make her hair pink, wanting to experiment with Vi's color pallete (from league of legends). However i decided to try something else in order to paint something more orignal. I tried blue and greenish blue before deciding on making her ginger. I just thought it looks cool and it fits her character after seeing it on her. As for the rest of the colors i thought. Ok what compliments orange? And i went with blue for the eyes and that greenish blue for the goggles, colors that are pretty much complimentary to her hair color. So its mostly a lot of observation and experimentation. Anyway i'm still trying to get better at this process myself. But i hope this helps for now . Cheers!