Make sure you have the necessary funds available on either your credit or debit card.
Conduct an Internet search with the keywords "pay," "taxes," and "online." Once you've picked a website, locate the state or county to which you pay your taxes.
Determine if online payment is an option. If not, you may also try to find out whether a "pay by phone" option is available.
If you are able to pay online, enter your information exactly as it appears on your property tax bill. Make sure that the site uses some sort of secure mechanism to transmit your information.