Gears List for Trekking

Clothing (Head)
Forage or woolen hat: - You can wear it in accordance to the changes in the Weather.
Sunglasses: - Never buy a cheap one, buy genuine UV protection glasses and use hard case to keep them safe.
Clothing (Upper Body)
Light weight long sleeve trekking shirts: - It may be useful for protection from sun and can be washed easily.
Long sleeve heavyweight shirts (cotton): - Warm and light to wear at night and early morning. Good for sleeping sa well.
Windproof Jacket: - Useful in case if wind picks up.
Rainproof Jackets: - Should be small enough to be packed in a tiny pocket.
Bra: - Sports Bra for Women (Synthetic not cotton).
Underwear tops: - Synthetic light weights, not cotton.
Clothing (Lower Body)
Underwear (4-5): - Pack both cotton and polyester underwear.
Lightweight trekking pants: - Make sure your pants are of synthetic, loose fit and have a good zip. Never carry or wear jeans.
Windproof / Rainproof pants: - Made of Gore-Tex and has full side zipper.
Clothing (Hands)
Gloves: - Always carry windproof gloves
Clothing (Feet)
Light weight hiking boot: - Hiking boot with a good traction sole. No new shoes if new “walk then in” to avoid blisters. Also bring spare laces. 
Light weight rubber shoes/ sandals: - Especially for toilet walks, showers at night time.
Hiking socks: - Carry both pairs of thin and thick socks of high quality.
Gaiters: -Useful for covering the ankle and lower leg in case of problem.
Equipment and Other Accessories
Backpack: - Find a pack that fits you well with all your essentials and hold all your gears. 2500-3000 cubic inches should be good (minimum size).
Luggage locks
Sleeping Bags: - (-15 degree bags will serve in most treks)
Day pack: - A small bag typically made of a strong, waterproof material to carry personal requirements for the day such as soap, quick dry towels, washing powders, toothbrush, tissue paper etc.
Water bottles
Water purification tablets or drops
First Aid Kit: - containing paracetamol, burn/bites cream, small bandages, and antiseptic creams.
Torch with Batteries
Wallet to carry money as trekking brings lots of changes on the way.
Plastic bags: - to keep things, dirty laundry.
Trekking map (Small)
Extras (Optional)
Trekking bars, candy
Camera, batteries, and chargers
Swiss Knife
Chewing gums, Mints
Pen/Pencil and Notepads
Unnecessary Things to Carry
Hair dryer
Shaving foam
Make up
Solar showers
Short Treks (7 kg)
Medium Treks (10 kg)
Long Treks (15 kg)
(Note : The above is according to the general rule depending on the needs, treks and the climate)