C - Compressibility
To maxmize space compress items as small as possible that aren't required during the day like you sleeping bag and misc clothing. Dehydrated food will cut down on space and weight significantly but doesn't offer the same nutrients as fresh food. Try and include some fresh food with your meals, the extra weight is worth it.
G - Gongshow
Pack with the idea of a slim and compact unit, avoid attaching loose items to the outside of your bag and secure items such as water bottles firmly and balanced to your pack. This will help you avoid those awkward snags of tree branches while on the trail.
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