Leo Said:

I want to start a small home-based business in teaching ESL (english second language)?

We Answered:

My suggestion would be to speak to an accountant and a lawyer to check on the home-based business requirements for your area and also the best way to set up your business (eg sole operator etc). Also check with your local council or state government agency as there may be restrictions or special requirements for operating from home in your area. Many have websites that contain relevant information.

After you've got it set up, join some networks - local business leads groups, chamber of commerce etc - so you can get the word out. If no-one knows you're there you're not going to get any business no matter how good your service! :)

I would think that certification would only be necessary if you intend to give the students some sort of qualification at the end of the course.