Find a library that doesn't charge library fines. Some cities and towns have eliminated late fees to encourage patrons to use public libraries and to cut down on administrative costs.
Set email reminders in your email calendar or put a reminder note on a calendar or on the fridge. Whether you use high-tech or old-fashioned methods, find a way to remember. Make sure to set your reminder at least a day or two before the due date.
Ask the librarian about the reminder options that the library offers. Some libraries will email you or call you prior to the due date. Other libraries offer you the option to renew online after you register with your library card number and password or pin number.
Take advantage of library "forgiveness" days. Many libraries have one (or a few) days a year where they will "forgive" any library fines. Check the library calendar for these days.
Go to a library that has lower fees if you can't find a no-fines library. The price range of late fees can vary at different libraries. Finding a lower "price per a day" late fee will make your overall payment more manageable.
Negotiate with the librarian. If you have a large fine, talk to the librarians about reducing it. If you've returned the item and the fines are more than the "lost item" fee, discuss this with the circulation desk.