I write about my day.  I write about my feelings.  I write down 'little things' or 'inside jokes' that I would never remember otherwise.  I tape tickets and receipts and programs into the pages.  I don't have the money or space for souvenirs, so these tokens become them.  

It is hard to stay committed to it.  I am usually very good about taking the time to write every day... but on my last trip, I did not do very well.   I was having fun.... I was reading Game of Thrones... I was lazy.  I could beat myself up about it, but why bother?  I tried, and at the end of the day, I still have most of our trip catalogued.