I made a picrew compilation of which ones I feel like are the most accurate to me.
imgflip.com/i/8yv5p1
My hair is a bit complex so here's a tip: I use clippers to keep the sides short. So if I have my hair back or styled flopped over all one one side, that part shows. I keep that shorter part my natural brown hair color. The picrews with the heart and chicken are pretty good resources for it my hair is back or on one side.
If my hair is down or not swept to a side, you won’t see any of the short brown. You will only see the green and purple.
The hair on the top part of my head is green. The purple is for any hair behind my ears (so like the back part of my head). The shade of green and purple doesn't matter, because I like to change it sometimes to be lighter or darker.