It is impossible to walk silently through dry and dead leaves. Even deer, the masters of stealth, can't do it. However, you can reduce the sound you make in a few ways.

1) Plan your steps and avoid the larger leaves and twigs.

2) Take slow steps, meaning lower your foot slowly.

3) Wear softer soled boots/shoes so that while lowering your foot you can feel hidden twigs and shift your step before commiting your whole weight, thereby reducing the chance of breaking twigs. The sound of snapping twigs seems to carry further than that of crunching leaves.

4) Roll your foot on the outside edge from heel to toe when stepping. This spreads your impact and can reduces stepping sounds.

5)Change the rhythm of your steps. A human walking normally makes a distinctive sound in the woods that no other animal duplicates. Spend time listening to how a squirrel or deer moves in the woods and try and do the same.

Hope this helps. I spend a lot of my hunting time slow stalking and have killed some large deer and pigs walking in such a manner. By the way, two hunters will never be as quiet as one.

+1 for Pighunter - that about says it all. The best way to walk quieter is to SLOW DOWN!

It's so good to hear from mature, experienced hunters like PAshooter and PigHunter. I, too, was amazed at how much quieter I could walk when my hearing started getting worse.
PigHunter, the only thing I can add to what you wrote is that not only can two people not walk as quietly as one, but two people usually sound like three or four. Don't we all love sycamore leaves?

From what I have found, if I walk around barefoot I am totally more quiet than if I have any shoes on at all. Not only do you know if you are stepping on a twig, but also you find out quickly how to stifle a yelp when you step on as small barrel cactus. (yes, this is experience speaking, 90% of the hiking I have done in the States has been in the mountains of southern NM) no, it isn't always the most comfortable way to hike, but I never hike unless I am barefoot.
The next best thing I have found is Vibram Fivefinger shoes. They almost feel like barefoot, but not quite.
I simply model my friends here in PNG. They go barefoot, and are silent. I go barefoot, and I sound like a significantly smaller herd of elephants than anyone I have ever heard wearing shoes... I'm still in the training stage, and hope to be for quite some time.