Complex sentence: He was a long-time member of the famed theatrical Lambs Club to which he contributed drawings, scripts and personal appearances; and was the Official Toastmaster of the National Cartoonists Society which he served as President 1965-1967.
Split into simpler sentences: He was a long-time member of the famed theatrical Lambs Club to which he contributed drawings, scripts and personal appearances. He also was the Official Toastmaster of the National Cartoonists Society for which he served as President 1965-1967.