Work through these before adding products.
GENERAL
Store address, selling and shipping locations, currency and its formatting. Set the currency position and separators so prices read naturally.
PRODUCTS
The shop page, measurement units, and whether reviews are enabled. Decide on reviews now; turning them off later after customers have left some is awkward.
Set the placeholder image, which appears for any product without a photo.
SHIPPING
Create at least one shipping zone covering where you deliver, with a method and a rate. Without a zone, customers cannot check out for physical goods.
PAYMENTS
Enable your gateway. Test it before launch with a small real transaction.
ACCOUNTS AND PRIVACY
Decide whether guests can check out. Requiring an account reduces conversions; allowing guest checkout is usually right for a new shop.
EMAILS
Set the From name and address to something on your own domain, and check the templates. Order emails are the most-read messages your shop sends.
ADVANCED
Confirm the Cart, Checkout and My Account pages are correctly assigned.