Is the supplication for undressing to be said once or with the removal of each piece of clothing?

It is recommended for a Muslim to say "Bismillah (In the name of Allah)" when taking off clothes at any time and for any purpose, based on what Al-Tabarani and Ibn Abi Shaybah narrated from Anas (may Allah be pleased with him) that the Prophet (peace be upon him) said: "To conceal what is between the awrahs of the children of Adam and the jinn, when one of them takes off his clothes, he should say: 'Bismillah (In the name of Allah).'"