It's nothing fancy but I love to have these printed out, cut apart, backed, and laminated before the school year starts. I usually have a class set (with a couple of extras). Since I do a writing workshop and not so much a writing center, then I have them on each of my tables for the kids to reference. You can get my color reference sheet by clicking on my image. I will also be uploading my number reference cards in a few minutes.
Don't forget about the giveaway going on right now for an awesome e-course from Playful Learning worth $125!!