This 24 hours is about pushing yourself to imagine life two generations from now. You can do it by yourself or with others. A good way to begin is by going back 50 years. How does life today differ from 1962? What has changed? What has stayed the same? What is better? What is worse? Can you compare 1962 with 1912 and ask the same questions?
When you have looked back enough, look forward. Two hints here. First, decide if this is going to be what you expect to happen or what you want to happen. If the latter, notice if things you don't want to happen are intruding, let them go, and replace them with your positive vision. Second, feel free to stay the age you are now!
Pick a recent day and recall what you did. Then walk through that day again in your imagination and see it as if it could be, 50 years from now.
If you are doing this with a group, it may be best if you don't take part, but instead give the group the questions and suggestions above, pausing after each one to give everyone time to imagine.