Running instruction in readme incomplete

[ZooeyMiller]

The local running instructions in your readme (which I'm really glad you have 🙏) do not give any information about setting up a database, or what environment variables I should have. These things are important (especially when your site isn't hosted somewhere) as as someone who wants to look at your code, or check out the project, I have do some foraging into the code to work out what setup I actually have to do.