It is very easy to set up. You sign on to the member website. You go over to the right to the "My DVC Membership" tab. You click on the "Annual Dues" tab. You follow the instructions and set it up.
I don't remember, but I BELIEVE you need your Bank's Routing Number. That is easy to get. You just google "routing number ___________" and put in the name of your bank. Then you need a bank account, so you put in your bank account or checking account number, choose for it to be deducted on the first or the 15th, and authorize it.
I always use it, because, even as a monthly payment, I need to pay $630 per month or $7,500 per year, and $7500 is just a whole lot more spare cash than I want to come up with.
If you want to make additional payments, or pay it off sooner, like, using a credit card, you can do that, too. Either online or by calling Member Services. However, even if you go online and make the amount of payment for the month or ANY additional payment, it will apply that payment across the whole year, so it will just lower your monthly payments for the rest of the year, but won't make that monthly payment. They will still deduct the monthly payment for that month. If you call them directly, at least a week before they are set to deduct from your account, and you make the payment through a Cast Member, then they can set it so that it counts as your monthly payment. Am I explaining this in a way that makes sense?
However, I have sometimes gone into the program and made those extra payments, just to adjust the monthly payments to a level I want. And I have also gone and paid off the whole rest of the year, sometimes. If you do that, and pay off the rest of the year, they won't take any more out each month (since your yearly dues are paid off), but your bank draft arrangement is still in place and monthly deductions will start again on the following January. There have also been times when I had all my dues paid off for the year, and I sent them extra money (on 3 different accounts) to see what would happen. They just applied it to the NEXT year, and thus lowered the monthly payments a bit for the following year.
Having a monthly payment agreement counts, with Disney, as having all your dues requirements paid up. So, you don't need to worry anymore about it, as long as you make sure you have enough money in your account every month for them to make the deduction.