This procedure is based on APT facilities. You can however adapt it by downloading and installing manually the packages,
This procedure should be applied from a "root" (SuperUser) account terminal,
This procedure should also work for any Debian derived distribution (Xandros, Linspire, Ubuntu, PingOO...)

Depending on your exact Debian release (Woody, Sarge, Sid, ...), you might need to add an APT source in /etc/apt/sources.list.

For Woody: add the following line into your sources.list
    deb http://www.logic.at/debian/ i386/

For Sarge and Sid: the official archive should be sufficient. Otherwise, add the following line into your sources.list
    deb http://people.debian.org/~shaul/ staging/

Update the list of available packages using the following command:
    apt-get update

Actually install NUT packages using the following command:
    apt-get install nut

You might also need to install the following packages:
    - nut-usb: If you need USB drivers (newhidups or hidups)
    - nut-snmp: If you need SNMP driver (snmp-ups)
    - nut-cgi: If you need Web interfaces
    - knutclient: if you need a KDE interface
    - wmnut: if you need a WindowMaker, or generic applet, interface

Configure service startup: Edit the file "/etc/default/nut" and modify it as below

# start upsd
START_UPSD=yes

# start upsmon
START_UPSMON=yes

Sample configuration files are provided in /usr/share/doc/nut/examples/
You need to copy these to /etc/nut before applying the below procedure.

Configure data acquisition: Edit the file "/etc/nut/ups.conf" and modify it as below

[ups_name]
        driver = your_driver
        port = device_port

Notes:
    ups_name is further used to address the UPS. You might change it according to your wish, but            don't forget to also adapt it for the rest of this procedure.
    your_driver must be replaced by the right value, depending on your exact model (mge-utalk,                    mge-shut, newhidups or snmp-ups)
    device_port must be replaced by the right value.
        - For mge-utalk and mge-shut: the name of the serial port (ie /dev/ttyS0, /dev/ttyS1, ...)
        - For snmp-ups: the name of the SNMP Agent host
        - For newhidups: "auto" or whatever value as newhidups automagically probe for USB UPS.

Configure data server: the provided file "/etc/nut/upsd.conf" is already configured to allow local monitoring only. If you need to modify it, have a look at upsd.conf manual page.

Configure user profiles: Edit the file "/etc/nut/upsd.users" and modify it as below
         # Supervision user
        [admin]
                password = mypass
                allowfrom = localhost
                actions = SET
                instcmds = ALL

         # Protection user
        [monuser]
                password  = mypass
                allowfrom = localhost
                upsmon master

Notes:
    For security reasons, prefer to change "mypass" references above, but don't forget to also adapt it
       for the rest of this procedure..

Configure protection: Edit the file "/etc/nut/upsmon.conf" and modify it as below

MONITOR ups_name@localhost 1 monuser mypass master

Start all services (data acquisition driver, network server and protection) using:
    invoke-rc.d nut start

If all went fine, the following line should be displayed:
    Starting Network UPS Tools: upsd upsmon.

From now on, these services will automatically started at boot time.