Make sure you are logged in (you can do this with the blue button in the top right corner of the home page)
When logged in click 'View Profile' again in the top right corner.
On the right-hand side of the page you should see options to Renew your Membership or Change Membership Level.
use these features to renew your membership. If you want to change your membership level, select that option (ignoring comments about refunds) and work your way through this page before renewing. During the renewal process you will be able to change details such as boat numbers and email addresses.