To a student, the third factor is critical. If you cannot make the information your are selling relevant to their lives forget it. Rely heavily on practical applications of your material. Bring the real world into your classroom, not yours, the students. They need to see that an education matters to them right now, not in college or the job market.
Motivation becomes the fourth and most difficult factor in an effective introduction.
What in the world motivates students. If teachers had that answer, they would bottle it and become very rich. Get to know your students. What are their needs and wants. Become familiar with their interests.