There are some things which make us happy. When we feel sad we should remember what those things are and plan to get them. When experiences are responsible for our mood then we need to plan for them to emerge. Remembering what made us happy means being self-aware. Writing down our mood in different contexts would represent the base research for us to understand better what we should aim to. Writing, daily journaling, reporting on experiences that had contributed to that self-awareness. Here is another scope where PKM can have a positive contribution to our mood and to make us happy. Keep track of places, people, tastes, happenings, events that left a positive mark on your memories and store them safely as the most precious ingredients for happiness recipes.