Good overall picture of what of server needs in terms of maintenance.

I was able to easily install the Microsoft Exchange Server in our Active Directory which is a functioning Active Directory.
However, I find that some crucial server maintenance work are not being accomplished.
The setup of our Exchange Server is very simple having one Exchange Server in a single domain and maintenance should not be that much of a problem.
What I need now is detailed information in order to have a good overall picture of what of server needs in terms of maintenance.
I understand that there are maintenance work to be done daily and maintenance work to be done on a monthly basis. Please help.
