I've had fun changing out the picture or saying to coordinate with my decor or the seasons. I get lots of inspiration from Pinterest. I've found that I like the looks of the board better if I just erase the board and not wipe it down with a wet rag (as I used to do when I taught school). I pull up a picture on my computer, pull out a piece of chalk and draw, sketch and write until I have it just the way I want it! You could use stencils if you wanted it perfect, but I like the freehand look, as well as the time to be a little artsy.
Here's what I did with my board last week, anticipating Valentine's Day:
With love from my country porch,