Here are mine...
The first one I developed was 18x24 and sat on a low easel, but I found a breeze would blow it over. I then printed it on 8.5x11 sheet and sandwiched it between a sheet of aluminum and plexiglass mounted atop an aluminum square tube staked into the ground.
I now carry this little sign (half of an 8.5x11 sheet flipped to landscape mode) in my glove box and put it on the dash behind the windshield whenever I'm at a cars & coffee or any other show.
And here's another display sign I probably found on this board and saved because I thought it looked nice.