Collier had a hodgepodge of jobs; he was primarily a schoolmaster, but taught privately, and acted as hedge lawyer, composing letters, wills, indentures, and other documents, in order to supplement his small income. He became notorious for his squibs, satires, poetry, and practical jokes. Later, he became a renowned caricaturist. Collier considered any sort of steady work "slavery" and preferred "liberty in rags." He wrote under the pseudonym Tim Bobbin, and some of his more politically sensitive works were printed surreptitiously. He aimed his satire at the standard targets of the day (fops, courtiers, lawyers, etc), but he was most scathing towards wealthy clergy and pluralists. His verse was considered "vulgar."