She sat for many sessions. Literally. She was a chair model.
Just before marrying Darrin Stephens, Samantha landed the biggest gig of her career: She was central to the roll-out campaign for the line of matching leisure-wear and upholstery, Chairmoflage by Arthur.
Few mortals ever saw the results of Samantha's modeling career, but it was one of the reasons many of the Witchkind were unhappy that she decided to live among the mortals--and even build a family with one. They thought it was foolish of her to not only put her promising future as a Witch on hold, but to also walk away from her fame and fortune as a chair model.
(If you enjoyed Bewitched [which this post featuring photos of actress Elizabeth Montgomery riffs off], and you also enjoy roleplaying games, you might find "Secrets of the Witchkind" a source of inspiration for a different kind of campaign. It was written by yours truly.)