My favorite thumbnails in learning about color:

 

It's not easy to choose the colors that will work together, even with the help from the ProCreate Harmony tool. Although I sometimes like the dark backgrounds, in my choices I see I like the lighter colors better.  Also, finding the colors that are close to each other in hue is not easy. I took the time in a couple of them to redo the tints to better match. 

This class was so fun to see how to choose and find colors that fit together. Thank you.

 My final one, an analogous illustration:

And here's my initial study of color palettes: