I keep a post-it note at my desk of a line from a well-known hymn as a constant reminder about God's faithfulness. Whether stressed about work, what's going on at home or the list of things that I need to do, this little note serves as a constant reminder about where I can give all my worries to.
"Morning by morning new mercies I see. All I have needed thy hand hath provided. Great is thy faithfulness, Lord unto me."