1) Open Firefox
2a) Click "Tools" 2b) Click "Options"
This is the first screen of Options. On this screen you can change your home page. This is a basic tutorial so not all options are covered here.
3a) In the Home Page section, type in "home.megagate.com"
3b) For the next section of options, click "Privacy" at the top (Marked 2 below)
In the Privacy section you can customize how long Firefox will remember your visited pages, cookie options, and private data.
4) Click "Clear Now" at the bottom right
5) Choose the options you would like to clear, and click "Clear Private Data Now" on the bottom.