Though it’s common practice to trim your wick before burning, DO NOT trim your wick before the first burn. This is going to give you a bigger, hotter flame that will melt the wax across the entire top of the surface of the candle, instead of simply in the center.
For this first burn, make it your mission to ensure the entire top of the candle has been properly melted before you snuff out the flame. The bigger the flame you have at the start, the easier this is going to be.
In addition, burn the candle long enough to melt the wax over the entire top of the candle. You see, when you burn the wax, it becomes softer and easier to burn the next time.
If only the wax around the base of the candle is melted when the candle is blown out, this is the wax that is going to melt faster and easier the next time. The more this process is repeated, the less of a chance the hardened wax around the outside of the candle has to burn. Remember your first burn sets the tone for the entire candle, and it’s up to you to make sure it burns properly.