Hi @helem I am not sure if all nebulisers are the same, mine(pari eflow) you just put 4mls of 7% saline in and turn it on, then breath slowly deeply on the mouthpiece until the steam stops, then huff cough to get up the mucus, steralise the handpiece then you are done. Its scary at first but you will get the hang of it. Hope this helps Heather