To reach the north summit it is pretty easy, the climb is short and beautiful, this is where peoples stop normally in winter. For the south summit there is a long ridge to climb. It is not too difficult as there is a cable all the way, but sometimes in winter the cable can be snow covered. The climb is exposed sometimes and requires a good technic with crampons. Do not underestimate this, as you also have to go back to the north summit then.