New Admin/Enginner to be….need help!

I am in the process of teaching myself NT and all associated software such as proxy, sql server and I am also teaching myself SCO. My question is, as a new admin/engineer what should I pay most attention to as far as being an Admin of a NT system.What processes should I go through on a daily/monthly/yearly schedule. Any help would be very appreciated.

Thank you all in advance.
Joe Blaylock