Born in Kvinnherad, Myklebust took a law degree from the University of Oslo in 1967, before starting work with the Norwegian Welfare Services (1968 to 1971). After that he worked at Norsk Hydro from 1971 to 2001, the ten last as chief executive officer. After he retired of CEO of Norsk Hydro he took over as chairman of the board of Norsk Hydro (until 2004) and SAS Group, as well as deputy board chairman of Norske Skog.[1]