This is a video I put together for All Outdoor, and covers the basics of setting up a backpack for a day hike.
In short, keep the most used items within easy access. This usually means an outside pouch of the backpack. This is where I keep the maps, compass and water filter.
Least used items go in the main compartment. This is where I keep stuff like food, stove, cook pot… etc.
The pack in the video is a three day assault pack. Read my first impressions of the pack here – Three Day Assault Pack First Impressions.