[header] How to decorate candles [title] Melt a crayon over the top of your candle. [step] This one gets a bit messy (actually, most do), so place a layer of newspaper under your candle or somehow get it to a protected surface. Then you can start melting! [substeps] Light a different candle--not the one that's getting decorated. 
Alternatively, you can use a lighter or a fireplace lighter as the source for your flame. Start melting a colored crayon with your flame on top of the candle.