To make this design of Christmas ball ornament you will need a rotary. I used the RA2 rotary. This method will work for at least red, shiny and matte balls (I haven't tried other colors yet). Also this will not work on sparkly balls. CAUTION plastic Christmas balls are made out of pvc which can possibly put out toxic fumes and cause corrosion to the laser. Though I haven't had any problems with it. Modify/use as you wish.
If you want to design your own version of this you will need to reflect your engraving vertically and rotate it as shown in the download. If you put the motor side of the rotary towards the left Make sure to change your origin to the center of the project. To modify the text you will need to ungroup it first.
After you have removed gold/metal colored piece on top by carefully pulling straight up on it. Put the long steel rods into the closest holes on the rotary chuck and tighten them down onto the neck of the ball. Tighten it just enough to hold the ball firmly. Then align the red laser crosshairs with the center of the ball.
Go ahead and engrave the ornament.
After you have removed the ball from the chuck replace the gold/metal colored piece onto the bulb, and now you have a finished ball ornament.