Criminal case fees are generally flat fees, where the fee has to be paid in full before I make an appearance in the case for you. In some matters, I may accept payment of the fee under a payment plan, depending on the type of case and any upcoming court appearances.
Civil case fees (including domestic) are charged by the hour, and require a deposit into my trust account to cover work to be done in the case. Periodically, you may have to replenish the trust account balance to continue to retain me, and so we are not sidetracked with any issue having to do with payment.
Although I accept cash or checks, I also prefer to use an online billing system, where you can conveniently pay using a credit or debit card.