Keeping a short wick is key to getting the most of your candle.
Trimming your wick will avoid mushrooming, which can result in unnecessary soot. In other words, it will make for a cleaner burn with less smoky residue.
Wicks that are left long or crooked can also result in uneven burning, flaring, and dripping.
Trimming your wick also optimizes the size of the flame. When your wick is too long, the flame is bigger and burns the wax faster. This will make you go through your candle faster with no added benefits.
How to trim your wick?
Before every lighting, you should trim your wick to be approximately 6mm (1/8 to 1/4 of an inch) long. All you have to do is use a wick trimmer when the candle is cool.
PS: You should not burn your candle for more than 4 hours at the time!