Chrome:


1. Right click the Chrome shortcut on your desktop, select properties


2. At the end of the target field in properties, add a space then -incognito

- add right after the end of the line. (see below)

- Click OK when finished



Firefox:


1. Right click the Firefox shortcut on your desktop, select properties


2. At the end of the target field in properties, add a space then -private-window

- add right after the end of the line. (see below)

- Click OK when finished