1. Select the menu located top-right of the browser’s instrument bar
2. Select Options
3. Select the Privacy panel
4. In the Tracking section, select the relevant button if you want to inform the websites that you do not wished to be tracked
5. In the History section, select the option Use Customized Settings from the drop-down menu and modify the following settings according to the desired managing of cookies:
   
   • Accept cookies (by selecting the relevant button);
   • Accept cookies from third parties (by selecting one of the following options from the drop-down menu: always, from already visited sites, never)
   • Keep until (select one of the following options from the drop-down menu: until they expire, until Firefox is closed, or ask every time).
6. In the History section it is also possible to select the button Show cookies if you want to remove the cookies that are present in your computer.

For further information, please visit the dedicated Mozilla webpage