Okay, so I have a confession to make. As a historian I totally tell people that they need to write their stories down. . .usually go as far as saying please write it in your own writing. I usually say that because as an archivist I want to see writing samples, it is fun and can tell a lot about a person through their samples by way of grammar and spelling and such. Besides writing styles are always fun to look at. . .
My confession is as follows, I don't write in a paper journal. Now, with that said, I do write in a journal online that is private, but there is an option to have it published in a book. I stumbled across the site while I was perusing facebook. It is the best thing that ever happened to me because I can't write very long without pain in my hands. So as I have gotten older (this makes me sound really old but I'm not I am 27 and have fibromyalgia) I have accepted the fact that sometimes these things have to be done in other ways, and my other way is typing. Whatever way you need, keep a record of your life, others will be thankful to know you through your writing.
My favorite site for writing is here. I also know other people who keep a blog and print out each entry they write. The options are endless!!! SO get pen and paper, or your computer or even a sketch book and start writing or creating!
One little after thought is that an "entry" doesn't have to be grandios or verbose, just write what you feel, and even if it is a sentence or two, it will be worth while. It will also become easier over time.