Early in his music career, Stept worked for a local publishing house as staff pianist (song-plugger), then in vaudeville as accompanist to performers that included Anna Chandler, Mae West, and Jack Norworth.
Their first hit came in 1928 with vocalist Helen Kane's rendition of "That's My Weakness Now," and the duo would collaborate on tunes through the early 1930s.
Stept worked with many other lyricists through his career, including Sidney Mitchell and Ned Washington (while songwriting for Hollywood from the mid-1930s to mid-1940s), Lew Brown, Charles Tobias, and Eddie DeLange.
Some of his popular tunes for the big screen are "Laughing Irish Eyes" for the 1936 film of the same name, "Sweet Hearts" for Hit Parade of 1937 and for the 1942 movie Private Buckaroo, "Don't Sit Under the Apple Tree" and "Johnny Get Your Gun."
Songs written by Stept have been recorded by many other big names in pop and jazz, including, Sarah Vaughan, Glenn Miller, Fats Waller, Louis Armstrong, as well as by Henry "Red" Allen, Bunny Berigan, Count Basie, Fletcher Henderson, and Josephine Baker.