This post is written for Brandon E, but it has broader application.
For me, among other things, “Jesus is Lord” means that when Psalm 1 says that the righteous man delights in the law of the Lord and meditates on it day and night, that Jesus is the Lord and His law is that we should love one another as He loved us. That is, because of the truth “Jesus is Lord,” we know who “the Lord” is from Psalm 1 and we know His law from the Gospels (such as John 15:12).
If I am constantly thinking about how to love others as Jesus loved us, and am acting upon the results of my thinking, then I am actualizing the lordship of Christ in my life. I am by that process making “Jesus is Lord” more than a lip service statement.