I had to do this for my job as a trainer. I think they chose the subject for me.
I had to do 15 min microteach on retail. I could do what I wanted! So as I have experience in retailing to clients I did a "do's and don'ts" of retailing. I aimed it towards therapists who needed help with sales.
Make sure you are prepared, I had to do a powerpoint and I had it on a disc and a usb just incase one didnt work! I got there and neither worked because of thier software! BUT.... I had also printed out several handouts of my presentation which I had given to the people observing so I wasnt stood there trying to do it from memory! Although I didnt show them I could use powerpoint they were impressed that I had backup so that is something to think about.
Do they want you to do a demo? In a previous presentation I did I had to do a demo so made sure i was prepared again with handouts and powerpoint but with equipment as well.
Topics could be anything but I know what its like when you are trying to decide, so heres a few I would consider:
How to look after skin
How a certain product works(if you are going to work for a product house make sure you research the product)
Theory of a treatment
Quick intro to the skin
How to cleanse
Retail
Painting a nail
Options are endless!
Remember, be prepared in every way and know what you are doing inside out! Practice inthe mirror, to a friend, boyfriend, mum, dad, etc!!
Good luck!!:Grope: