"There are no small battles for those who don't come home." Dad was a Veteran of WW2 and Korea. He would sometimes say this to himself while watching the daily Vietnam headcount on the evening news.
I remember a couple of things from my grandfather, my dad, and other important people in my life. The key to being effective was "Measure twice, cut once." The behavior to avoid was "Ready, fire, aim!"
A couple I've used frequently over the years.
"You can't make chicken salad out of chicken ****"
"What the **** were you thinking?"
Dad always got right to the point
Whenever my Dad would give me a hard or impossible task, he would say "You can do it, I've got all the faith in the world in you." And I would say "Anything's easy if someone else has to do it!" Then he would say "Yep." and I would just have to get started and get it done.