Remove admin privileges to users

Currently all users have admin privileges in Cognos. We would like to restrict the permissions on some of the folders to some users. Inspite of restricting permissions like write access to the folders, the users have all privileges as everybody is an admin. Can someone guide me how to remove admin privileges to some of the users in Cognos?
I tried removing ‘everyone’ from ‘System Administrator’ but that prevents the users from loggin in. Please guide.

start with reading this.

this is a 8.4 document but for Cognos 10 the priciples have not changed