I tend to analogize questions about keeping the Lord’s Day with questions about how we should date. As Christians, our attitude about both should be positive. We should ask regarding dating, “how can I best honor the Lord on a date?” The moment we begin to ask what teenagers typically ask, “How far can I go?” or “What can we get away with?”, we’re on the wrong track and headed for trouble. So we should ask, “How can I best honor the Lord on His day?” (especially when we are the ones who are going to be the one receiving the blessings).
The best way, obviously, is to spend as much time in corporate worship as I can – morning and evening if at all possible. This also forms a wonderful bookend in that I’m beginning and ending the day in the way I hope to spend eternity. In between worship services, prayer is always good, as is bible reading, or the private or family reading of edifying Christian books. Meditating on the Lord and His word and work is also always a good practice.
I also encourage Christians to fellowship on that day, enjoy table fellowship and discuss the sermons and other matters of faith and life and pray together. There are also wonderful opportunities to exercise mercy here; are there singles or the poor whom you could invite over for a meal or someone you could visit and pray and read with in the hospital or at a retirement home? There is no end to the ways you could bless others and honor the Lord on His day if your heart, mind, and soul are set in that direction.
Personally, I don’t scold people for taking naps (unless it’s during worship) or for allowing small children to go out and play, but I tend to ask adults to primarily be thinking about how they can make this day special and make “Holy to the Lord” the inscription they write over their Sundays.