The above photo is of my Guerrilla Intactavism kit that lives in my purse at all times.
Post-It notes in a bright color
pens and/or markers to write with
and, my personal favorite, WASHABLE dry-erase markers!
Just toss these items in a plastic bag or makeup bag (I found a zipper pouch CHEAP at Target) and there you go! I leave messages via dry-erase marker or Post-it in every bathroom I visit, on every gas pump I use, and just about anywhere else I can think of to leave them! I will be posting about more location ideas in the near future. :)