When packing a backpack for an extended trip, the key is to make sure that you have the right gear for each area of your trip by packing it in a certain way. Here are some tips:
-Your sleeping bag should go on the bottom of your bag because it's large and heavy and can damage the rest of your gear if it's loaded on top.
-The next layer should be your tent and other items that you won't need until you're ready to set up camp, such as ground cloth and stakes.
-The third layer should be clothing that you'll need in camp – extra socks or hats, etc., along with any food or water that you'll need on the trail.
-In the middle sections, divide your gear between electronic devices (camera, GPS, laptop) and non-electronic gear (books, water bottle, toiletries). These are things that will stay with you throughout the trip but you don't want to access every day.
-The final section should be things that you'll access regularly during your hike – snacks, map, first aid kit. Pack these all in ziploc bags for easy access.