Executive Summary
pkg - net/isc-dhcp3

    # pkg_add -r isc-dhcp3
    # cd /usr/local/etc
    # cp /pathto/dhcpd.conf .
    # touch /var/db/dhcpd.leases
    # mv /usr/local/etc/rc.d/isc-dhcpd.sh.sample /usr/local/etc/rc.d/isc-dhcpd.sh
    # /usr/local/etc/rc.d/isc-dhcpd.sh start
Finished

more later

dhcpd.conf