Read more books - If you’re not a reader, now would be the time to start. Reading is one of the best ways in life to build and develop empathy and an understanding of others.
Read better books - If you’re already a reader, challenge yourself to read classics you’ve been avoiding. Plow your way through some Tolstoy or Dickens (or if you’re me, Jane Austen).
Write a book - They say everyone has at least one book in them. Actually sit down and write it.
Volunteer for a charity - Work in a charity shop. Volunteer for a suicide help line. Spend the time and money that you could spend on a gym membership or weight watchers on helping people in need.
Learn to knit or crochet - Knitting, crochet and other crafts are proven to be excellent stress relief, and at the end of it you have a new thing. Challenging patterns and writing or designing your own help to keep math skills and logical reasoning sharp.
Knit or crochet for charity - If you already know a craft, there are a lot of charities that collect hand-knit (or crocheted) items. You can make squares for kids in South Africa, or hats for premature babies, or toys for child victims of crime or disaster.
Plant a garden - Grow your own food. If a whole garden is too much, just make the effort to keep a few plants in your house alive and well.
Treat others the way you wish to be treated - Be mindful of your actions and attitudes, and how they can effect others. Question the decisions you take for granted as being “good” things and examine whether you truly are making the world a better place, or whether you are merely maintaining the status quo.