It may sound strange but with this project you should start now if you want to make till upcoming Christmas. This is a Christmas tree light where each lamp is controlled by individual microcontroller. Now you can start counting how many PCBs needs to be made and soldered to make a long garland.
Actually this doesn’t look as difficult as it may sound. Each lamp here is a RGB LED controlled by tiny PIC12F609 microcontroller. All LED boards are chained with three wires where single master MCU controls the show.