My goal, as I learn how to be a better self-published author, is to do all my own artwork. This is one of the advantages I have over working with the other publishers I have published books with. Page Publishing, to be fair, did use my artwork. But they also controlled the cover design (since that was what I was paying for).
Planning to publish two more novels this winter, I am working ahead to create effective covers. So let me show you how I fumbled together a cover today.
Here are the artwork elements that I started with;

I then put the elements together with a photo-editing program.

I then added the finishing touches with the paint program.

I can probably be satisfied with this result. But I am a fickle artsy-fartsy type who will probably fuss it all up well before I actually use it.