Nima what platform are you using?
Is it PHP or ASP? And any specific CMS?
With wordpress all you have to do is to install a redirection plugin and you are good to go... but if you have a normal php based website you have to write the following code in your .htaccess file.
_Redirect 301 /oldpage.html http://www.yoursite.com/newpage.html_
_ Redirect 301 /oldpage2.html http://www.yoursite.com/newpage.html_[](http://www.yoursite.com/folder/)
If you are on a ASP platform you have to look in to your IIS and then work accordingly.