Track Guest Checkout orders in Magento 1.9.x

yourdomain.com/sales/guest/form/ – change yourdomain.com with your domain name

Customer can get their order information after providing the following details according to the specific order:

1) Order ID
2) Billing Last Name
3) Find Order By (Dropdown Value as Email Address/ZIP Code)
4) Email Address/Billing ZIP Code

Fill all above information and press Continue button.

Customers who used the guest checkout can check their orders online by using the link above & it will show Orders details and it has linked as “Invoices” top of this page and once they click on this link it shows the order details and print invoice link at the bottom of the page.

Here they can lookup their order by the order ID. If the order is paid, there will also be a link to the invoice available for the customer to print. Please note that invoices are only created upon completing the payment. So this link won’t be available if the order isn’t paid yet.

To setup automated emails for orders and invoices go to:
System > Configuration > Sales > Sales Emails > Order and
System > Configuration > Sales > Sales Emails > Invoice