In an article by Suzanne Rose, originally published on www.helium.com, she offers some tips for mystery shoppers on what NOT to do during a shop.
Avoid being overly dramatic
While shopping, don’t act like you’re in a school play. Making loud comments that are not genuine will draw too much attention to yourself. When talking with employees or sales clerks, appear casual and nonchalant.
Do not draw attention to yourself
Blend in with the crowd. You don’t want to stand out too much but, instead, you want the employees to treat you like any other customer. We’re looking for the experience of a typical shopper. You don’t want the clerks to think of you as someone special or unusual.
Do not appear too knowledgeable
Even though you may have learned a lot about the store from your your mystery shopping report beforehand, you don’t want to show you know more than the average customer. Your goal is to have the employees explain things to you or serve you the way they would any other shopper.
Don’t sit in the store writing down the details
Feel free to take a few notes if it is something a regular customer might do, but you don’t want to appear out of place scribbling in a notebook. Try to remember as much as possible and write down your notes after leaving the store.
Don’t tell anybody
Don’t tell anyone in the store that you are a mystery shopper. It might be tempting to tell a fellow customer, but don’t risk it. An employee may overhear you or that customer may spill the beans to someone else.