These examples will use wlan0 as the example device. I am changing the IP address from 10.1.1.196 to 192.168.1.100.
Turn on the device
# ip link set dev wlan0 up
Get device's current IP address
# ip addr show dev wlan0 2: wlan0:
mtu 1500 qdisc mq state UP qlen 1000 link/ether 84:3a:4b:0a:cc:cc brd ff:ff:ff:ff:ff:ff inet 10.1.1.196/24 brd 10.1.1.255 scope global wlan0 inet6 fe80::863a:4bff:fe0a:cccc/64 scope link valid_lft forever preferred_lft forever
Optional: Remove the device's old IP address
# ip addr del 10.1.1.196/24 dev wlan0
Give the device a new IP address
# ip addr add 192.168.1.1/24 brd + dev wlan0
The "+" is shorthand, and auto-sets the broadcast address based on the IP address and netmask. E.g., the "+" above means "192.168.1.255"
Give the device a default route
# ip route add default via 192.168.1.1 dev wlan0