In 1877 he became an apprentice sign painter and continued in this line of work for several years, nurturing a desire to become a professional cartoonist.

By copying the work of cartoonists, he acquired the skills necessary to gather a portfolio, which gained him an interview in May 1883 with Joseph Keppler, the director of Puck Magazine.

[3][4] After two and a half years at Puck (from May 1883 to December 1885), Zim moved to Judge magazine, directed by Bernhard Gillam.

Like many contemporary cartoonists, Zim generated cartoons of all varieties, including some which could be considered offensive for their ethnic stereotypes.

The illustrious painter William Merritt Chase, on a visit to the offices of Judge in 1897, voiced his praise for Zim's artistry and related that the artist Edwin Austin Abbey pasted his work in a book.