How do I descale the Bambino Plus?

The machine signals it needs descaling when the 1 CUP, STEAM, and 2 CUP buttons flash alternately for 15 seconds. Turn the machine off, then press the 1 CUP and STEAM buttons simultaneously for 5 seconds to enter descale mode; fill the water tank to the DESCALE line and add descaling agent. Press 1 CUP or STEAM to begin the cycle, and once complete the machine will go into standby mode. Note: never remove or completely empty the water tank during descaling. (Page 15–16)