These are just some of the things I do protect my privacy online. I am always open to learn. So, please keep those suggestions coming.
1. In Firefox,
Tools->Options->Privacy Tab->Under Privacy Data
Select the option “Always clear my private data when I close firefox”
If you want to pick and choose what exactly firefox clears out everytime you close it, click the “Settings”
button next to the option you just selected. I usually select all options other than the “Saved Passwords” option.