Even tho I went to school for Advertising and design, my love for illustration and comic books has over the years pushed me into the realm of illustrator. (Tho most of my day jobs have been design jobs.) Much of my approach to posters is taken from what I learned in advertising, is it an interesting concept? does it meet the right mood for the client? does it tell a story? Would it look good on a wall? I'd be the first to admit, that I don't always meet all the criteria, but aim for epic, then settle.