Complex sentence: He eventually served as best man at Constanten's wedding., but while his bandmates and friends were using cannabis, LSD, and other psychedelics, McKernan preferred alcoholic beverages such as Thunderbird and Southern Comfort.
Split into simpler sentences: He eventually served as best man at Constanten's wedding. While his bandmates and friends were using cannabis, LSD, and other psychedelics, McKernan preferred alcoholic beverages such as Thunderbird and Southern Comfort.