how to make a non-root user as superuser

[harshavardhanreddy mandeepala]

hi
I am using Linux fedora core 3.
how can i make a non root user as a superuser.
when ever i enter into system as a non root user by  login ,the user
must be super user.

if u have a solution plz mail me to   hvreddy1110 at gmail.com

thanks in advance

Regards
M.Harshavardhan Reddy