Tobacco will absorb any aroma or fragrance that it comes in contact with. Paper and sulfur based matches or the use of a fluid based lighter can leave the cigar with an unpleasant taste. The preferred method to light a cigar is the use of a butane based lighter. A lit wooden match can be used once it has burned off the chemicals used in the ignition process.
Once the cigar is cut, hold the open end of the cigar over your flame and slowly rotate it. This will "Toast" the cigar and prime it for lighting. While it is still warm, place the cigar in your mouth and hold it at a 45 degree angle over the flame. Slowly puff and rotate the cigar while maintaining slight contact with the flame. A good cigar will light easy and burn evenly.
Credit: CigarHandbook.com - Your Guide to Cigar Smoking