From the top of the Grand Montets cable car, ski down the very start of the Point du Vue piste before quickly ducking the rope and heading skier's right and down the Glacier du Rognons. Take care to watch out for some large crevasses on the upper section. Keep to skier's right of the Rognon itself (a large rock island). This soon brings you down onto the Glacier d'Argentière. Skin up the glacier to the foot of the north-east slope of the Col des Cristaux. The first 300 meters are barely 45 degrees before the slope steepens at the top. Ski back down the same way and out onto the Glacier d'Argentière.
Be aware that this face has a strong easterly aspect to it and can heat up surprisingly quickly in the morning and often releases wet slides in the spring.