If you are using Google Chrome to disable cookies:

1. Go to 'Tools Menu'

2. Click on 'Options'

3. Click on 'Under the Hood'

4. 'Cookie Setting' should be selected. Once done select 'Block all Cookies'

Now all cookies should be blocked on your Google Chrome.

To clear existing cookies:

1. Go to 'Tools Menu'

2. Click on 'Options'

3. Click on 'Under the Hood'

4. Under 'Privacy' section select "Show Cookies'

5. A new window should open called 'Cookies' In here you can see all the cookies within your Google Chrome Browser.

6. Click on "Remove All" to remove all traces of cookies. If you wish to only remove a certain cookie, simply highlight and click "Remove"

This procedure will stop sites from installing cookies on your Google Chrome browser.