Chrome
To open an incognito window, start Chrome and click the wrench icon in the top right corner of the screen. Click New Incognito Window and start browsing. Alternatively, you can press Ctrl+ Shift + N to bring up a new incognito window without entering the Chrome settings menu.
Firefox
To enable private browsing in Firefox, click on the hamburger icon at the top right and then select New Private Window. You can also just use the CTRL + SHIFT + P keyboard shortcut. You will be able to tell you are in private mode because of the mask located in the top right of the window