Make sure the setting is appropriate
There are some places that should be completely off limits to selfies, like funerals or the scene of an accident. Most situations like this are pretty common sense, but as a general rule, ask yourself if taking a selfie in a given situation could upset or offend people who see it. If the answer is yes, save your selfie for another time.
Funerals, weddings, and other major occasions are off limits. If you are at an event meant to focus on or celebrate another human being, put down your smart phone and step out of the limelight.
Similarly, if you are at a memorial site, keep the phone in your pocket. Dont take selfies at a memorial or statue, especially if a tragic event took place there once before.