do's and don'ts
The general rules and regulations of a given activity, operation, or situation. Before you begin your first day working for us, there are a few important do's and don'ts that I need to familiarize you with. Tom doesn't understand the basic do's and don'ts of social etiquette.
do’s and don’ts
n. the rules; the things that should be done and those that should not be done. I must admit that a lot of the do’s and don’ts don’t make much sense to me either.