If you take the package tour to the place like Lhasa, Gyantse, Xigaze, etc. with the altitude of 3000m, you don't need to provide the special equipment only the daily commodity required. Please find out the below list as the daily commodity which is required to be prepared for your Tibet tour:
Sun cream with the protection index of 60, sunglasses or dark glasses with a sun protection factor of 15, the lip creams and balms with SPF rating, towel, a pinch use toothpaste as a substitute, electric torch, rope, Swiss-style pocket knife map. When planning your clothing needs for your tour to Tibet, remember, your destination sightseeing is at elevation of 3500m and your cloth must be warm enough and can be removed easy enough.
Jacket: a fiber-pile jacket is ideal for evening.
Sweater: Wool or wool mix with a high neck for extra warmth.
Headwear: wool or fiber-pile ski-style cap or balaclava for warmth. A lightweight brimmed hat is good for sun protection .Inexpensive broad brimmed straw and felt hats are sold in Tibet's city markets.
Scarf: wool or silk is best.
Mittens or gloves: wool is best.
Bandanna or handkerchief: Bring several.
Cotton underwear: four or five pairs.
Socks: at least three pairs.
Shirts: A long-sleeve shirt made of wool, flannel, or chamois, or a track-suit top. A long-sleeve cotton shirt for warmer temperatures. Bring two or three T-shirts as well. Pants: For men, one pair of loose-fitting wool pants, wool knickers, or fiber-pile pants, and one pair of light-weight cotton pants. Women should wear a mid calf dress or skirt, though pants and knee-length knickers with socks are also acceptable. Shorts are not appropriate at any time in Tibet for men or women.