Starting by never watching any news.
If I see it here that is the extent of my news knowledge. Because.... What am I going to do about any of it? It happens it happens. Shootings, hurricanes, Wars, etc. Later on when some charity at Costco is asking for money I will find out and gladly give.
It is something that I feel keeps me from ever getting depressed. Don't even know the feeling.
Besides here I know little about most major world events and I don't care. Just don't care.
That is step one.
Care about the people around you and who you know first. Then try to take care of the world second.