The wider the candle, the larger the wick, if it is a really wide pillar, you may need multiple wicks. This is just something you put on the end of the wick to keep it down. They sell metal ones at craft stores, or you can tape it to a penny. The main trick with a pillar is to leave it alone once you pour it. A pillar can take several hours to harden.
Pillars are also fun to play with.
Try putting some ice-cubes in with the wax, and enjoy the interesting holes when the candle is done. To remove a pilar from a mold is simple. To remove it from a carton, just cut off the carton. One warning about cartons, though. If you use one, the seams on the carton will be evident on the candle.