I book over the phone in September for a trip in February 2016. I paid 15 % deposit and the rest is payable on or before 30 days before departure date
Once you book over the phone and get a booking reference, you then create a my Disney account on the website which corresponds to the country you booked with. I live in Ireland but I booked through the French call centre to get the French offer, so I created a My Disney account on the French website.
You can then access your booking online and can pay the balance online