Before the days of cell phones, iPads and other mobile devices, photographers would use small notepads to record locations, frame number, settings, and other such important information about the photos they captured. Today, you can use your phone as a notepad.
For every trip I take and destination I visit I create a note on my Apple iPhone® or iPad®. Although my camera will record all of the details about the settings for each photo, I continue to record data about location, best time of day for the light, weather conditions, what I saw, and any other information that may be helpful later. In particular, I rely on these notes for writing captions, naming and organizing photos in case I forget the location, and for writing the articles where the photo might be used.
So take notes and take lots of notes to help simplify your writing, captioning and organizing later.