Kingdavid
What I do is I tell myself
1. They may not know it is assur. When they do things that are wrong they do it beshogeg while I do it bemeizid.
2. If they know it is assur they may not know how serious of an issur it is.
3. Even if they know it is serious they may have a huge yetzer hora to do it and it is very hard for them to stop. I know that there are things that I have problems with that I have a very hard time stopping.
4. Hashem doesnt appreciate when we look down on others and my looking down on others may even be meakeiv my tefillos from being accepted so I better mind my own business and stop thinking about what they are doing wrong.
Start saying the tefillah of Reb elimelech of Lizhensk before Davening Shacharis and have kavana by Aderaba Tein B’Libeinu Shenir’eh Kol Echad Ma’alas Chaveireinu V’Lo Chesronim.