The prospect of going on a trip invites all sorts of daydreaming. Over the last year or so, my wife and I have fantasized about our honeymoon in Paris. We’ve used language learning programs to burnish our high school French, accumulated a worrying amount of cookbooks about French cuisine, binge-watched French TV shows on DVD, and read piles of travel memoirs. But at a certain point, the dreaming must stop and the planning must start.