Garnish plain pillar candles with leaves for elegant and understated fall centerpieces. Choose a few favorite leaves from your lawn. Determine placement of leaves on each candle. Coat the backs of the leaves with decoupage medium and smooth in place on the outside of the candle. If necessary, use tacky white crafts glue to hold the stems down. Cover the sides of the candle and the leaves with one or more coats of decoupage medium.