The idea is to: Create & Customize Your Own Writing Paper - this is just a tumblr post, so here are the directions, as written on Pinterest:
To create “washed out” pictures, I copied and pasted a picture onto Word, selected “Format Picture,” selected “picture,” than under “image control” and “color” dropdown box, selected “washout.” Print and write your letter! This is amazing!
One more thing - did you know, you can type on the same paper?! Now, I realize that loses a little of the personalized appeal due to lack of your own hand-writing. But, how cool is this?! All you have to do is - once your picture has been changed to "through text" - insert a text box and starting typing to your heart's content.
There's no rule that says you have to use lined paper either. In fact, the lined paper was a tad (very tad...like, barely noticeable tad) difficult because it was smaller than my printer paper drawer sizing. It did work, obviously, but it isn't an absolute must other than the cuteness factor of it.