From My Account Page
Go to My Account page, after logging in, you will select “My Orders” from the options on the left hand side. Once there all of your orders will be found on that page.
From Email Notifications
You should receive two emails when you place your order. You can find your order number in both emails.
The first coming from the payment processing company, firstname.lastname@example.org. The order number is found in the email subject line and under invoice number.
The second coming from the website to confirm your order, email@example.com. The order number is found in the email subject line and in the email (in green).