This is Rae from the Shopify team. Congratulations on launching your store!
It's definitely a great idea to test your checkout process to make sure everything is working correctly, and I'm happy to help suggest a few different ways to do this.
If you're using Shopify Payments, you can put the gateway into test mode and use a test credit card to simulate a purchase. Here's how to get started with this:
You can also use Shopify Payments to simulate a failed transaction, too. If you're interested in trying this, just enter in these payment details to the checkout.
If you aren't using Shopify Payments, you can still create a test transaction by using Shopify's Bogus Gateway and following these steps. Or, to place a real order via the Bogus Gateway, you can follow these steps instead.
Now that your site is fully launched, I also recommend reviewing our store launch checklist. This is a really helpful way to quickly double check all of your store settings and options, to ensure everything is set up correctly.
Please keep me posted on how these tests go, and let me know if you have any questions along the way!
I wanted to check in with you and find out if you had a chance to run any test transactions on your site? If so, how did these go?
Let me know if you ran into any troubles, or if you have any further questions and I'll be happy to continue helping out!