How do I clear everything out of my computer?

I know how to delete browsing history and use my system tools. But how do I clean it out really good so no one can find things I saved and deleted, things I downloaded then deleted, and things I searched and erased. I mean get rid of every little thing. How do I do that?How do I clear everything out of my computer?
a really good program for shredding everything histories cookies temp filesetc ... is webroot window washer theres even a wipe freee space function that will eliminate any and all traces of deleted filesHow do I clear everything out of my computer?
Hi, hit the link a very good free program
bring gasoline and matshes


put some gasoline on your PC


and put up fire on your PC


finally you will find your PC very shine
Use a shredder program to delete files from the individual directories including the history and temporary internet files folders etc.
To delete all your actions got to windows history


cntrl+H


here u delete everything .


that's it

use of mensovit plustablet