You need to register to OMPT to purchase a test attempt.
Once you have logged in to the platform, please click on STORE in the blue bar at the top of your screen. You will then see a list of products. You can either purchase a test attempt, practice material, a mock exam or all three at the same time by purchasing the bundle.
Once you have made your selection, click on "Add to cart". Next click on the green button labeled "Proceed to checkout". You then have to agree to the terms and conditions, after which you can click "Proceed to payment".