Unwind your fairy light strand and stretch it out until it's straight. Then slip the lights down into the bottle one by one.
Line the battery holder up with the neck of the bottle and wrap some tape around to hold it in place.
Put the batteries inside your battery holder, making sure the + and - sides align with the markings on the box. Plug in your Circuit Playground and flip the switch to "on" to make the lights glow.
Put your Circuit Playground and battery into the clear plastic box so the lights shine through the clear side.
Put your bottle lamp on top of the box to catch the lights and make the rainbow lights shine into the bottle.
Put your bottle in a dark room or on a windowsill and enjoy your beautiful lamp!