Luggage and bags:
Take a good, comfortable backpack, and avoid any 'hanging' item (bags, bottles, etc), in order to keep your hands free.
Clothing/Shoes/Weather Gear: Trekking boots, sandals, windbreak jacket, Polartec jacket, short pants, hat. In winter, add to the list: helmet, Polartec pants and balaclava, plastic mountaineering boots, rackets, randonee skis (optional).
Toiletries and Medical Supplies: Band aids, aspirin,high factor sunscreen, if you're going to the glacier: acetazolamide to prevent AMS (Acute Mountain Sickness).
Photo Equipment: A good manual camera is ideal in winter (low temperatures freeze automatic one's batteries). Wide angle lens, a medium telephoto or zoom lens, polarizing and skylight filters. Cable release for long-time exposures at night. 50 or 100 ISO film is perfect.
Camping/Beach/Outdoor Gear: This is absolutely a camping place, so bring: tent (3-season for summer; 4-season, expedition-class in winter), camping stove, , In winter, besides the eventual mountaineering technical gear, add to the list: ice axe, crampons (both needed to climb the glacier in any season)
Miscellaneous: Headlamp, extra fuel (no liquid water around in winter), GPS, VHF transceiver tuned at 150.625 MHz (Mountain Rescue). No cell phone works in there (just VHF radio and Satcoms)
Luggage and bags: During the winter, the weather can get very cold. When I went up the canyon, there were 7ºC at noon. So bring up warm clothes, a nice scarf, and something to cover your head. It can get cold, as shown in the picture. Frozen water and snow can be seen everywhere.