For deposit, DraftKings and other sports betting sites accept any major credit or debit card, including Visa or MasterCard. They also allow you to deposit via PayPal. Furthermore, gift cards from major organizations like MasterCard or American Express can be used for deposit only.
Withdrawal methods tend to be more limited. DraftKings provides withdrawals to linked bank accounts and PayPal accounts. Typically, withdrawals will take a few business days while deposits are almost instantaneous in most cases.