You already know your worth in teaching one person...
Teaching more than one person is the same as teaching one person. It is a piece of cake.
Before the class you create a lesson plan where you write what you want to teach in the class.
To new students, you then explain the rules of the "game" drill, later for the same reason and make sure that the students area fully aware to their safety and their training partner's safety.
You ensure to provide a specific warm up starting with few jumping jacks, moving into stretching the spinal vertebrae, warming up major muscle groups, squats, push ups, and sit ups, front and rear neck rolls are good if you are going to do some grappling, and then finalize with stretching of the legs giving it a greater range than the kicks to be practiced in the class.
In the more complex sparring you want to have 2 people spar at the time and have the whole class learn from it to ensure maximum safety and attention. You do a warm up before class, the same that you would do yourself to minimize unnecessary injury, and then you correct one person at a time.
As you correct one person at a time, you stop the class to ensure that you control it and everyone is listening so nobody else would repeat that mistake so you do not have to correct the same mistake again.
You demonstrate the techniques with a volunteer student, in full speed at first. You then demonstrate if in slow speed if needed, and break down the techniques to steps that are easy for the student to perform according to their level.
If you organize your class, think about safety in training, and think about how to bring another human being that has two legs, two hands and a brain, to do the same simple things that you are capable of doing by showing them and making it easier for them to learn from your experience, you should have no problem in teaching a class.
Over the course of 45 minutes or the length of the class, try to stop by each student and either correct or comment them for their performance. It really is a piece of cake.
Krav Maga - Use Your Body as a Weapon!