How do I connect to wifi using only the command line in Manjaro?

I recently updated my system with Pacman and am getting a could not start kdeinit5 error message. After some Googling. It seems I simply need to update Pacman. However, as I am on Wifi and have no means of connecting via Ethernet. I need to connect to my WPA2-PSK protected network before Pacman will function. I'm a new Manjaro user. How can I connect to my network?