If you have ever taught children, you have likely observed them look to a certain place in the space above them as they try to recall something they have studied. Students have better success with that effort if the thing they're trying to recall had a position in their classroom, a place-marker of sorts.
To help my students remember these key properties, I created a triangular sign that you can see below~you can imagine the other faces of the sign.
To create this sign, I purchased a plastic core to which the properties were attached. You can find it here: http://www.ffr-dsi.com/tr-94-triad-mobile-kits
I created the signage on Microsoft Publisher, saving the finished files as jpegs. Here's a link to those I made: Associative Property, Distributive Property, and Commutative Property. The finished jpegs were then sent to be developed as 8 x 10 pics from my favorite printing destination: Costco. Finally, I attached the finished sign to one of our Hang-Mates and placed it in a prominent position. And yes, when it came time to test these properties, you can guess that I enjoyed seeing my students look to the spot where this sign used to hang, remembering the lessons I taught.