docs: add imposter syndrome disclaimer

Author: njncalub

README.md

@@ -26,6 +26,18 @@ Public decks for the **We Will Craft** classes.
 
 3. Open http://127.0.0.1:8080/.
 
+## Contributing
+
+**Imposter syndrome disclaimer**: We want your help. No, really.
+
+There may be a little voice inside your head that is telling you that you're not ready to be an open source contributor; that your skills aren't nearly good enough to contribute. What could you possibly offer a project like this one?
+
+We assure you - the little voice in your head is wrong. If you can write code at all, you can contribute code to open source. Contributing to open source projects is a fantastic way to advance one's coding skills. Writing perfect code isn't the measure of a good developer (that would disqualify all of us!); it's trying to create something, making mistakes, and learning from those mistakes. That's how we all improve, and we are happy to help others learn.
+
+Being an open source contributor doesn't just mean writing code, either. You can help out by writing documentation, tests, or even giving feedback about the project (and yes - that includes giving feedback about the contribution process). Some of these contributions may be the most valuable to the project as a whole, because you're coming to the project with fresh eyes, so you can see the errors and assumptions that seasoned contributors have glossed over.
+
+(Copied from [Adrienne Friend](https://github.com/adriennefriend/imposter-syndrome-disclaimer))
+
 ## License
 
 This project releases under the [MIT License](./LICENSE.md).