A good packing job can make a big difference on how your pack carries. This is especailly true with internal frame packs.

Be sure to pack the load firmly. Lot of energy is wasted compensating for constant shifting of load. If your pack has compression straps, use them!

Think about what you'll need during the day and put these items at the top lid or outside pockets and/or at the top of the main compartment so that they can be easily removed. Don't forget to make sure your maps, compass, rain gear and flashlight should be easily accessible too.

Use color-coded stuff sacks to help organize large undivided compartments.

Remember, the higher the weight is in the pack, the more upright and comfortable your walking position will be. But it will also have a greater effect on your balance. So find the compromise that works best for the terrain you will be on.