[groovy2shoes]

I haven't used i3 in a long time, but if it's got support for systray icons, you can run the NetworkManager applet and manage your network settings there as you would in any ol' desktop environment.

I do this with awesome, and it works well. It's a one-liner in rc.lua:

    awful.spawn.with_shell "nm-applet"

Also good for volume control applets :)