You will first be asked for a Userame and your email.
You will then get an email back from the site asking you to set a Password. (If you don’t get an email back, check your junk mail.)
Use the link in the email to set your Password.
You can then login with either your Username OR Email …….. Plus your Password.
Or even easier, just Register/Login using your Facebook details by pressing the Login with Facebook button. If you are already logged into Facebook the system will recognise you from there.