As someone who's a bit candle obsessed-I've said it before, but there really isn't a better, easier, more instantaneous way to create a sense of ambiance in your home-I burn through them very quickly. In an effort to rein in my candle budget (while tea lights and tapers are generally pretty cheap, the bigger pillars and scented varieties add up really quick!) I found a few tricks to make them last.
Wrap candles in foil (which keeps the wicks from getting soggy) and chill them in the freezer for a few hours to slow down the speed with which the wax melts.
Always make sure the wicks are trimmed short: ¼ inch or less. If the wick is too long, the flame gets out of control and you burn through wax really quickly. If you see smoke or flickering, it's time to blow out the candle and give the wick a trim.
The first time you use a candle, let it burn long enough so that the wax has liquefies all across the surface to avoid tunneling, which is when the wick starts to burn and recede into the rest of the candle (which wastes a bunch of wax in the process).
Keep candles away from drafty areas, like windows or near ceiling fans. This can cause them to burn unevenly-and less efficiently.