There are several puns in the title of this thread.
"Planning to Grow Old" can involve how we live while we are still young and "Gracefully" can mean "full of God's Grace", not just physical gracefulness.
One of the things I have noticed about our elders, from a childhood in which they normally sat on porches watching us kids play, through an adulthood where I worked with elders in caregiving centers (both day centers and homes) and also where I have had a chance to see a revival of home-care, one thing I noticed is that the life-changes were planned for, among the "successful". I put that word in quotes because I do not mean the financially well-provided old age, but just the peaceful, tranquil old age.
Bringing home devotionals into more practice is a very important part, because as an elder's ability to cope with change increases, and memory problems arise, the home devotional can be a stabilizing element, allowing younger relatives to participate in visits instead of just awkwardly sitting around feeling sorry for the old guy (or gal). During those moments our elders are still alert and able to impart some wisdom to us while we are able to listen.
The beauty of a well-designed home devotional is important to good health in old age, too. The familiar face of Mary and a few fresh flowers gathered from the garden or picked up at the grocery store can cheer an otherwise lonely setting. My dad used to take pictures of the little shrine he had set up every time he put new flowers in it and send them to me, 2,000 miles away. I felt as though we shared a decade of the rosary every time he did that, and I imagine he was saying a decade for me when he did.
This is just one example of planning to grow old gracefully. I am sure you all can think of some, and share them with even the youngest children, help them imagine their own old age ahead of time.