Always take a before and after picture:
Build your portfolio 
For reference: to help with your lash map while clients eyes are closed.
Most important… to have for your records.
Once lashes are lashed , everything around the eyes, inside the corneas, the lash counts, the surrounding of the skin will be more noticeable. Clients will look at every flaw and every flaw will be more noticeable that were not noticeable.

Ex: this client complained about her right eye white part of her inner corner is red from the lashes and it has been 4 days, it hasn’t gone away. She demanded that she needed a refund will go to doctor. But with proof, her before picture had the same red eye.