This could be potentially dangerous if you lose daylight without having found a safe campsite, so count on being able to get to your campsite before sundown and have a backup in mind in the event that it takes longer than expected to get to the goal camp. Food, of course, should be your first item. Enough rations should be packed to last the duration of your hike with a little extra in case of emergencies. And even if you plan on hunting or fishing, there should still be enough food packed in case the wildlife is less than cooperative. Any foods in containers should be light, meaning not made of glass, and no cans.
Plastic can be a hiker's best friend, as can powder drinks.
Clothing is a rather important item to consider packing, but it shouldn't be overdone. Remember that whatever you want to bring with you is going to be packed on your back, so packing light is a good idea. Suitcases are frowned upon. Bring enough to stay warm and dry, but remember to pack some lighter clothing for extreme temperatures. Be prepared for any weather.