The essential role of an advisor is to challenge students' ideas of what they want to do with their life. Emphasis should be placed on activities which strengthen the student's ability to think creatively, critically and independently. An integrative approach in answering research questions and participating in interdisciplinary collaborations is key to success. In laboratories and departments that regularly produce good scientists and engineers, some very complex mentoring is going on, and it is almost always a group activity.
Students: Find something you love doing, and interact with people in that field who are in touch with their sense of passion about their work.