Navigate to the WooCommerce > Settings > Payments page and select "Astral Payments". Set the "Use Testnet" checkbox to enabled and save your changes.
If using the Terra chrome extension, ensure it is set to "Testnet". The payments page will inform you if you are connected to the wrong chain for your test payment otherwise.
Add items to your cart within your eCommerce store and go to your checkout page. Select the Astral Payments method as your chosen payment gateway.
After selecting your payment gateway and placing your test order, you'll be redirected to the Astral Payments testnet gateway that shows the details of your payment to be made for your purchase.
Click "Pay" and you should be prompted to confirm a transaction within your Terra chrome extension for the amount required for your purchase. Wait for the payment to succeed, at which point you will be redirected to the order confirmation page for your store.
The order should now be completed and your stock levels adjusted within your WooCommerce store.