Before you publizise your shop, you should test it.
To do that, visit your shop and double-check its design and the products' presentation. Order some products as a test and carry out the payment. Verify that everything works as desired and that you receive emails from the shop system.
Did the tests work to your satisfaction? Then delete any sample data such as products, customers and your test orders.
Now you can open your shop. Visit the page Settings >> General in your shop’s administration area, set the Shop status to Open and save the changes.
Now you can advertize your shop and prepare for the first orders to arrive.