Depends on the trip but here's a generic list (optionals in brackets)
-boots, woollen socks, shorts, t shirt, watch, sunhat, gaiters
-pack (75L), liner (plastic survival bag), sleeping bag & liner
-polarfleece jacket, polarfleece jersey, polar fleece beanie, polyprop bottom, waterproof jacket & overtrou, pack cover, toilet paper (gloves, daypack)
-spare socks, trousers, polyprop top (polyprop bottoms & top, towel, jandals, spare t shirt)
-headtorch, toothbrush/paste, (hut tickets, cards, deodorant sorry yes that is optional only)
-2L platypus water bladder, compass, map, camera, mug & bowl, fork/spoon, sunblock, insect repellent, chapstick, strapping tape, spare plastic bags, (foam mat)
Group gear
-aluminium pot, pot handle, gas cooker, lighter, gas, first aid kit, pocket knife, (Macpac Olympus tent, candles)