We’ve covered why “Do Not Track” isn’t a silver bullet that prevents you from being tracked. However, if you don’t like being tracked and want to express that preference to websites, you can enable “Do Not Track” in every browser.
To Google’s credit, future versions of Chrome explain exactly what Do Not Track does when you enable it. Remember that, by enabling Do Not Track, you’re just expressing a preference. Websites may or may not obey your preference.
Mozilla Firefox
In Firefox, click the Firefox menu button and select Options.
Click over to the Privacy tab and enable the Tell websites I do not want to be tracked check box. Firefox will send the DNT: 1 HTTP header whenever you connect to a website.
Google Chrome
When this article was written, Google was on the verge of adding Do Not Track to the stable version of Chrome.
To enable Do Not Track in Chrome 23 and later (the unstable versions of Chrome, when this article was written), click Chrome’s menu button and select Settings.
Click the Show advanced settings link at the bottom of the Settings page.
Enable the Send a ‘Do Not Track’ request with your browsing traffic checkbox.
To enable Do Not Track in Chrome 22 and earlier (the current stable version of Chrome, when this article was written), install the Do Not Track extension from the Chrome Web Store.
Internet Explorer
In Internet Explorer, click the gear-shaped Tools button, point to Safety, and select Tracking Protection.
Select Your Personalized List and click the Enable button. Do Not Track is now enabled – Internet Explorer sends the Do Not Track signal when you enable any tracking protection list, whether it contains any entries or not.
Opera
In Opera, click the Opera menu button, point to Settings, and select Preferences.
Click the Advanced tab in the Preferences window, select the Security category, and enable the Ask websites not to track me checkbox.
Safari
In Safari, click the gear button and select Preferences.
Click over to the Advanced icon and enable the Show Develop menu in menu bar checkbox.
Click the page button, point to Develop, and enable the Send Do Not Track HTTP Header option. if you’re using Mac OS X, you’ll find the Develop menu on the panel at the top of your screen.