Firstly, don �t feel worried! Every teacher in here has had the same feeling as you about a new class at some stage. The thing to remember is that they probably might feel worried too about learning a new language or making mistakes mistakes in front of their colleagues or managers. It is natural to feel apprehensive going into a new environment and having to teach a group of people that you don �t know. However I am sure that with your help, these low-level English speakers will both develop and benefit from your classes! After the first class, you �ll feel great! 

The link below is a great first class for business English, giving them some useful new vocabulary and teaching them how to introduce themselves, which is very important in business. Give this plan a try - they �ll love it!