Here is a suggested packing list for a backpacking trip:
be aware that each person will not need wach item, but be prepared to carry 25 pounds of food/water and gear per person.

Big 4: Sleeping bag, Tent, pad/mattress, Backpack
rain gear
extra clothing
insulative clothes
warm hat
extra socks
extra socks
extra socks
food
water purifier/filter
cooking stove, fuel, etc...
pots/pans
dish
cup
eating utensils
map&compass
sun & bug protection
bandana or handkerchief
flashlight
first aid kit
fire starting kit
repair kit/tools
knife.
personal hygiene kit (with  TOILET PAPER)
binoculars/camera
rope to hang food