Amp up your choreography. You have subbed enough and you know what your classes like and what needs work. You may have limited your dance routines to the Salsa and Cha-Cha. But your classes want to learn more. Add the Merengue or the Cumbia. Don't forget the Mambo and some Reggaeton. Your class will love to feel that they are learning something really exciting.
Switch out your music. This means more work for you, but that is also what is fun about teaching a dance class. Mix up the music. Add some Latin music from more mainstream musicians. You will want different beats and types of music in your class.
Practice your routines. Everyone forgets and makes mistakes and you will too. It's OK. Laugh it off and keep going. Don't take it too seriously but make sure you know most of your dance steps.
Allow your students to express themselves. Leave parts of songs open to interpretation. They don't have to move their arms exactly the way you do. They may use the wrong foot starting out. They will catch on and catch up.
Teach your class the basic steps before you start the song. Go over the steps several times. This will help your class gain confidence and they will be able to relax and enjoy dancing to the music.
Laugh and enjoy your class. When your students see you having fun, they will have fun, too. Zumba is a healthy way to have a great time and get a cardio workout to boot. Zumba!