My wife has been practising daily gratitude journaling in the evening (using pen and a paper journal) for about 2-3 years, writing down her thoughts, and also a few things she is grateful for.
She says reading back through it is a lovely experience - so much nicer to be focusing on that over doom and gloom.
I've decided to join her, as I can clearly see how it has benefited her mental health. All this is is a personal diary that is used to note and later reflect on meaningful moments in one’s life, however small.
They don't have to be particularly epic things - just small moments that would otherwise be forgotten. She says it shifts focus onto positive happy things - you start to notice more things about your day, however small.