I couldn't find any Baymax ornaments at Disneyland or at Hallmark so that left only one choice. This ornament was incredibly easy to make.
Clear plastic ornament - it's easier if you can split it in half
White acrylic paint
Paint brush - I like foam ones
Cover the ornament in thin layers of white acrylic paint, waiting until each layer dries before adding new paint.
Once the paint is thick enough to be opaque and it's dry, pencil on Baymax's eyes. Fill in the outline with the Sharpie.
The end! Easy as can be, and the result is adorable.