Avoid websites that provide pirated material. Do not open an email attachment from somebody or a company that you do not know. Do not click on a link in an unsolicited email. Always hover over a link (especially one with a URL shortener) before you click to see where the link is really taking you.
This is likely the most difficult thing to do on the Internet. Many hackers will access your files not by brute force, but through social engineering. They will get enough of your information to gain access to your online accounts and will glean more of your personal data. They will continue from account to account until they have enough of your info that they can access your banking data or just steal your identity altogether. Be cautious on message boards and social media. Lock down all of your privacy settings, and avoid using your real name or identity on discussion boards.
Click the menu icon "≡" at the top right of the browser window, choose More tools and choose Extensions to open the Extensions.
Uncheck Enabled to disable an extension or lick the trash can icon next to the extension you want to delete.
Click the Disable link under the plugin you want to disable.