Go to mid station at Auguille du midi. Traverse left towards the Montanvers. The last area before going over the ridge to the Montavers is right below the Spencer. You get a good view of it from the valley. This is the north side of the "wall" from Motenvers to the Auguille du midi.
Its not all that difficult to climb. On a good year you can boot it up. Once up the root finding is quite easy but its on glacier all the way. It can be up to 50 degrees steep depending on season. Normally the conditions during the run can vary quite a lot.
Glaacier al lthe way so were crampons and harness and bring the axe. Apart from everything else related to this kind of skiing.