The most important setup task you can do for your store before publicly launching it is to test it. Thoroughly.
My strong recommendation is to have WordPress open in one browser and then use a completely separate browser to test your site from a customers perspective. For example, if you use Chrome for your day-to-day operations, open up FireFox and use it to test your site as a customer. This will give you the most accurate representation of how a customer will see your site.
I also recommend using different email and mailing addresses for your test customer account compared to your WordPress administrator account. That’ll let you test each role and make sure everything is looking and working like it should.
Break things. Do your best as a customer to screw it up. This will show you what you need to modify or change as the administrator. If you can figure out how to find a hole in your system, then someone in the public will as well.
When you’re done testing, you’ll want to change your EasyPost API Key from the test version to the production version.
Congratulations, your BuyBack site is up and running!