I climbed Lanin 4 years ago. There was a number of regulations, and be sure to investigate it, before leaving for the mountain. You have to bring ice axe and crampons, warm sleepingbag, down jacket, warm socks, warm gloves/mittens, warm hat, fleece, warm boots, head lamp - and a radio or sat. phone. It is possible to rent a radio at the station.
The climb was pretty straight forward, but the wind was hillarious. People disappear on the mountain every year due to the ever changing weather. We stayed the night in a hut on the way up.
Good luck and enjoy.