From the parking cross the bridge and follow the ski du fond track south to Pre le Chalp, from here follow the torrent rif de Chatelard south west. At around 2063m head right up a steep sided ravine, follow this until it comes to a waterfall (marked on the map). From here either take the open slope on the left up or there is a small couloir on the right, both lead you up above the waterfall. Then pick a route up the slopes above either up a gully or the more open slopes to the west, at the top of the slopes turn east and climb up to the ridge and on to the summit.
Ski back the way you came up.