Nostalgia is gratitude that showed up late. Try to feel it while the thing is still happening.

Missing something is often the first time you properly value it. The feeling was available the whole way through; it just needed the thing to be gone before it could get through to you. That delay is the expensive part, because the warmth arrives when there is nothing left to do with it. Nothing stops it arriving early except that the present looks ordinary and the past does not.

Pick something currently in your life you suspect you will miss. A routine, a person, a room. Spend a minute inside it this week feeling about it now the way you expect to in ten years.