ip link (for example wlp0s29u1u3) /etc/netctl (vim /etc/netctl/tq84-wifi) with the following content. (Use ip link to find find interface name). Description='TQ84 wifi connection' Interface=wlp0s29u1u3 Connection=wireless Security=wpa IP=dhcp ESSID='the SSID of the wifi network' Key='the secret code'
netctl start tq84-wifi.