Once you have descaled the boiler and refilled your frontpiece of the iron itself (hopefully with distilled water - any supermarket) you press the "reset"/ "restart" button on the back end of the steam generating unit. When the water is hot enough press steam button & turbo button a few times - WARNING: make sure iron is facing downwards and cover ironing board with old rag because initially brown steam splatter will come out on first few steam releases.