Click Sign in / Register on the top right-hand side of our homepage, scroll down to Forgotten your password? and enter the email address which you used to register with us. An automated email message will be sent to that address with a link for you to reset your password.
If you need more assistance with this (for example, if you no longer have access to that email address), please contact us - we'll be happy to help. We can easily change the details of your existing user account - there's no need to set up another account if your email address has changed, or if you have moved job.