First, you'll need to drill a small hole in the top of each jar lid. It will need to be big enough to fit the power cord through.
After you've drilled your holes, thread the power cord through so that the light bulb sits inside the jar. Use a washer to protect the cord from the rough edges of the hole.
Next, drill 12 small holes in your timber. Pass the cord for each jar through a hole, so all your wires are hidden by the timber façade.
Next, get an accredited electrician to fit your masterpiece into your desired location. Decide where you want to hang your lights (the centre of the room, for example) and wire in to the electrical circuit.
This project should only be made under the supervision of an accredited electrician.