copywriters spend their days writing prose for the purpose of advertising to promote and sell goods and services. 

For example, a copywriter might write a new jingle for a cereal commercial, or come up with a new company slogan.  

TO become a copywriter you should learn the art of copywriting top book recommendations by digiriz (the copywriting magician )

  the wizard of ads  (for advance) 

the handbook of copywriting(for beginners ) 

influence: the psychology of persuasion