When you tell someone you will pray for them, actually do it. When you let words come out of your mouth, make sure you act on them. Do not use your faith flippantly. It's not just a phrase, it's a way for us to build each other up. Let us all watch what we say and watch what our actions show.
Side note.. pray for people who we wouldn't usually pray for.
Pray for your boss.
Pray for your coworkers.
Pray for your neighbor.
Pray for the people across the street you've never even met.