I had this exact same problem...

Use this space to let them know why you're qualified to help. Were you in the same place they are? Do you have some sort of experience doing the thing? What results have you gotten for people? Spill all the tea! 

Or, you might write a little bit about your teaching philosophy. You might even write a bit about where you learned your stuff, any certifications you have, what you believe in, how you work with your clients, etc. Again, don't be afraid to be repetitive here—most people aren't going to read every word on this page. If you can hit them with your expertise and experience in at least one of these sections, you've established the trust factor, which is all you need.

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