Are you referring to the self serve iPad tablet stations that AS is using and have replaced the old kiosks in some airports? My understanding is that you just use the tablet station in the same way that you used to use the kiosk. I always check in online and rarely check a bag so I haven't used any of them.
https://news.alaskaair.com/guest-exp...ilicon-valley/

Also see:
https://www.flyertalk.com/forum/alas...ologies-2.html