Step 1
Select "Manage account", which will open this page. Select the "Plan" tab, and select "Change plan".
Step 2:
Select a billing period and select the plan.
Step 3:
Click on the button "Add a discount code", enter it and click "Apply". Accept the Terms of Service, and then confirm this by clicking on the "Complete plan change" button.
To finish:
Click on the "Logout" button and login again to apply changes.
