A method for producing extreme ultraviolet light includes producing a target material at a target location; supplying pump energy to a gain medium of at least one optical amplifier that has an amplification band to produce an amplified light beam; propagating the amplified light beam through the gain medium using one or more optical components of a set of optical components; delivering the amplified light beam to the target location using one or more optical components of the optical component set; producing with a guide laser a guide laser beam that has a wavelength outside of the amplification band of the gain medium and inside the wavelength range of the optical components; and directing the guide laser beam through the optical component set to thereby align one or more optical components of the optical component set.