All the WADS have similar setups. All of them require basic info like company name, address, contact info, time zone, credit card number, etc.
Some WADS require funds up front, before they let you set up an account. Others let you set up an account at no charge, but you must pay in advance before the ads can run.
Usually there's a choice between manual or automated funding. I always prefer manual, so my funds run out before the credit limit does.
Since you'll be spending considerable amounts on the credit card, be sure that you know the monthly and daily spending limits on your card. You'll also want it to be a rewards card. Some credit cards give discount flights, or merchandise, but I prefer cash back.
Math Warning! For example, my top net earnings doing affiliate marketing full time was around $3,000 a day. I ran at about 20% profit. That meant a $15,000 daily spend on the credit card. So even a measly 1% cash back credit card results in nearly $55,000 cash back per year!
(Yes, you can do it too. Or even make more money than I did. I didn't start by spending 15K a day on ads. I started small with $500 as my total budget. Then slowly through persistence, patience and commitment, plowing 80% of my earnings back into the business, eventually got there.)
You'll need to make sure your bank and credit card company know what you're doing. Tell them in advance that you're buying advertising or you risk having your card blocked for sudden massive spending.
Finally, be sure to check the countries that are allowed to participate in the WADs. Almost all of them are worldwide, but I have run across a handful that allow only USA residents to advertise.
There is no passion to be found playing small, in settling for a life that is less than the one you are capable of living.