 His mother purchased a bass for him when he was 14 years old on the basis of a given promise that he would commit himself to learn to play the instrument.Clayton later changed school to the non-boarding Mount Temple Comprehensive School in Dublin, where he met future U2 bandmates Paul Hewson ("Bono") and Larry Mullen Jr., who were also pupils there, and was reunited with his childhood friend David Evans.In September 1976, Mullen put an advert onto the school's bulletin board seeking other musicians to form a band; Clayton showed up for the first meeting and practice, so did the Edge with his older brother Richard Evans ("Dik"), Bono, and Ivan McCormick and Peter Martin who were two of Mullen's friends.