Click Add to cart button on the products you wish to purchase.
Click Continue Shopping to continue add other products into the cart or click Checkout to proceed your payment for the products.
You'll reach a log in page where you need to log in your account using your Username and Password. If you don't have an account created yet, you need to register an account before you proceed your payment.
You'll need to confirm your shipping address on the Shipping Address page and click next button.
From here, you need to select your shipping methods and click next button.
Next you'll need to choose your payment method then click next button.
After the steps before this have been done, You need to reconfirm your billing details and agree on the terms and condition.