"Salient cues" are distinct attributes to something that ones pays attention to for a certain task at hand. This can differ from person to person, however. Take for example, a can of Pringles. The salient cues for someone health conscious would probably be the health and nutrition facts. However the salient cues for someone who just wants a snack could be only what flavor they are. If you have certain salient cues in your design that you want a use to pay attention to, make sure they are obvious enough for the user to expect those to be the cues.