My children were fortunate to have been given tablets for Christmas. Both were the same, along with matching cases.
To tell them apart, and also to provide them with a little more protection, I set out to make them covers.
I used a free tutorial from Create Kids Couture, which offers instructions for cases in several different sizes for different tablets.
My only change was to replace the elastics with cotton/lycra fabric I sewed into a tube. The elastic I had on hand was either too firm or much too narrow.
These work quite well, and my only addition will be to pop a velcro dot on the back of the tablet for added security.