There were numerous variations of style adopted by flappers in the 1920s, but the main points were short bobbed hair, short skirts (by the standards of the era, which generally meant knee-length), and a slim, flat-chested, boyish figure. Cloche hats and long strings of beads were also fashionable. One way to find some iconic photographs of flappers is to search for the names of famous actresses and socialites from the 1920s. Dorothy Parker and Zelda Fitzgerald were flappers, as were actresses such as Clara Bow and Louise Brooks. The photograph of Clara Bow attached below contains the classic attributes of the flapper, though it is a posed picture, with no evidence of cocktails, smoking, or jazz.
For these elements of flapper culture, photographs of 1920s nightclubs are a useful source. The attached article from history.com includes several group photographs of flappers and opens with one in which the girls are dancing alongside jazz musicians at New York City's Parody Club in 1926. The next photograph shows two flappers smoking and embracing their dates. Finally, the Saturday Evening Post featured many pictures of flappers, and the cover often featured drawings or paintings of the latest fashions for women, as shown by the archive attached below.