Fasting 6 Days of Shawwal
Ayyub (Allah be pleased with him) relates that the Messenger of Allah (blessings and peace be upon him, his family, and companions) said, “Whoever fasts Ramadan and follows it with six days from Shawwal it is as if they fasted the entire year.” [Muslim, Abu Dawud, Tirmidhi, and Ibn Majah; Ahmad transmitted it from Jabir, Muntaqa
According to scholars, one may fast any of the six days of Shawwal. Neither do they consider it necessary for a person to fast the six days consecutively. So long as one has fasted six days either consecutively or separately, he has fulfilled the requirement and he will receive the same rewards.