It is all aboout conserving energy. Choose a pace that you can comfortably do all day. Do not "stop and go". Getting moving is more difficult than a smooth pace of keeping going. It is a matter of conserving momentum. Step around obstacles, not up and over them. Rhymthic breathing - in other words set a breathing pace and let that determine your step pace. The goal is to keep a steady heartbeat. Just like gears on a car, slow down up hills, go faster on flat ground. Breath right. Foot placement matters - stepping on a flat surface is easier on your muscles than on a side-hill. Even on a steep hill, you can find little flat spots - try to utilize these. Relaxe. If you are tense or hurried you will waste a lot of energy. Start each day slowly and speed up gradually, then slow down at the end of the day for your "cool down". The start lets your system adjust and the cool down reduces sore muscles at the end of the day. The walking "lightly" is mostly a matter of flexibility - bend knees instead of stiff-kneed plopping down your feet. Pretend you are hunting and sneaking up on an animal. You will also notice that most long distance hikers use light hikers or trail running shoes, not boots. No sense in lifting 5 pounds every step!