Butane lighters: There is a small pin on the bottom where you can insert the butane nozzle to fill. After filling, allow the lighter to sit for 1-2 minutes, allowing the cold butane to adjust to room temperature before igniting. - Wick lighters: Remove the cap on the bottom of the lighter to expose the cotton, and fill the cotton with lighter fluid. Let the lighter fluid soak into the wick for 2-3 minutes before igniting. - Electric lighters: These do not need to be filled, and can be recharged with the included USB cable.