Don't be excessively cautious when facing life-changing choices
For important decisions (e.g. quitting a job or ending a relationship), those who make a change regardless of the outcome of the coin toss) report being substantially happier two months and six months later.
From a large-scale randomized field experiment in which research subjects having difficulty making a decision flipped a coin to help determine their choice. Heads or Tails: The Impact of a Coin Toss on Major Life Decisions
Career equivalent of musical scales
Recently, one of my favorite questions to bug people with has been “What is it you do to train that is comparable to a pianist practicing scales?” If you don’t know the answer to that one, maybe you are doing something wrong or not doing enough. Or maybe you are (optimally?) not very ambitious?