Attempting to change other people will always resented on some level by those you try to change.

Take peace seriously but not over-seriously; humour attracts. To this generation, exhortations to "do good for mankind" end up sounding like chores. Make the humour fit situation, time, and place, and you will win more minds with it than mealy-mouthed platitudes about peace.

Dampen any over-passionate allegiance to your own nation or church with a dose of rationality. It is no stain on your faith to use the rationality that your God gave you to use, whether you call it God, Allah, Yahweh, "The Light" or "Life-force" - or whatever you call the Divine. Inflamed passions blindly lead ahead; rationality takes two or three steps back to see more of the picture.

If you want to lessen TV watching, don't make a moral crusade out of it, for people who like their TV (and don't notice how bad the propaganda is getting) will react to that like drug users react to those stupid, unconvincing anti-drug commercials. No one wants to be told what to do, or that what they like doing is wrong. Instead you can be subtle: if you have a friend over and s/he says "Hey let's watch blah blah blah" think of some great thing to go and do that will appeal to this friend and suggest doing that instead.

Change yourself, for you can control what you do, but not what others do. But what you do can be either persuasive or antagonizing.

Hear what from the other ear when you speak.