Brush a layer of silicon gel over both sides of the leaves, covering them completely.
Drill through the center of the chestnut using a small drill bit. (You could use a nail and hammer to make a hole through the chestnut, but make sure the chestnut is semi soft so it won't split.)
Spread 3 to 4 leaves into a fan with the tops of the leaves in different directions. Center the leaves on the pillar candle.
Secure them with copper wire, circling the wire around the candle twice. (Leave enough room at the top for the candle to burn a few inches without hitting the leaves.) Twist the wire together to hold, leaving approximately five - inch - long tails.
String a chestnut onto one of the wire ends and slide it down onto the center of the leaves. Pull the second tail over the outside of the chestnut and string it through. Twist the wire tails together with needle - nose pliers to secure. (The twist should be small and delicate.)
Silicon gel is a heat-resistant material that protects the dry leaves form the heat of the flame.
Collect and press your fall leaves so that they become flat. You can keep them between layers of cardboard until you need them!