go to enable mode
> en
#
then configuration terminal
# config t
set an IP address
# interface vlan 1
# ip address (static.0.0.IP) (subnet.255.mask.000)
set a password for virtual teletype
# line vty 0 15
# password (type the password)
to go back
# exit
to enable, enable mode on virtual teletype
# enable secret 0 (password for that)
now enable password encryption in show run
# service password-encryption
set ip default-gateway
# ip default-gateway (type.the.ip.here)
to save the configuration
# copy running-config start-config