Turn off the lights or the corresponding group of light on the shield. Install a reliable support need level (a ladder, a table, a chair), so you can easily reach the place where you want to change the lamp.
Carefully remove the outer ring of the lamp with the spring-holder. Remove the blown bulb from the pin of the cartridge.
Compare the marking of a new bulb with the old - it should be identical. Hold the new bulb with a tissue or dry cloth. If you take the lamp arm, the bulb will remain fat fingerprints which can lead to crystallization of the quartz bulb and reducing the lamp life.
Insert a new bulb into the pin, push it inside the lamp to the desired level, strengthen antennae compressed in a spring-holder. The light should clearly hold on to the three tabs of the lamp. If necessary, tweak it. Refit the ring light.