CMA/Patient Care Tech Externship Advice...please

Hello all! I'm currently a Certified Medical Assistant/Patient Care Technician student during the day (course ends in mid Jan) and in the evening, I'm working on my prerequisites at the community college while I wait for a slot in clinicals..

Today, I received a call from a prospective externship site, Planned Parenthood.
I'm thrilled at the idea of learning more in regards to women's health, being involved in the community and just being supportive. I would love to hear from anyone who has completed an externship...I have to complete 80 hrs of hands on training in order to obtain certification & the diploma. I'm quite nervous and want to make a good impression. Any advice, tips and how to make the most of this externship experience will be greatly appreciated.

Thanks!