Demonstrate mutual respect first. In order to gain the appreciation of students, you must convey that you respect them. One way to do this is to show that you honor their differences in personality and coping mechanisms. Not everyone is wired the same and trying to force others into your way of thinking isn't respectful. In addition, showing courtesy for your students' learning styles and time commitments builds respect.
Know your subject matter. Since you are working on building respect within the confines of a classroom, make sure you know what you're talking about when it comes to the material you've been assigned. If you're nervous about teaching at first, cover the topics you know well and can answer questions about so your students get off on the right foot with you. If you are asked a question you can't answer, tell the student he's raising an excellent point that requires more research, or open the subject up to the class for further discussion.
Greet each day with a good attitude. If you're a sourpuss all the time, your students are not likely to respect you. They may tip-toe around you in fear but to truly admire and appreciate you as an instructor, show positivity about the learning experience. This doesn't mean you can't have a bad day from time to time, but even in those instances, be honest with your students about your mood and they are more likely to have respect for you.
State your expectations. If the rules keep changing for your students, they won't respect your or any of the regulations you set. Make sure you clearly write out what you expect from your students regarding attendance, notification of absences, making up for work and cheating. The more your students see that you can enforce healthy boundaries, the more likely they are to show respect in the classroom.
Commit to office hours and be available to your students. Showing your students that you are available and care about their concerns builds respect in the classroom. Show empathy for their situations, but don't let them fool you if you think you're being fed a lie. Strike a healthy balance of being a friend and mentor and you're likely to gain their long-term respect.