If he was conscious during the period when he abandoned Salah, he should make up for the missed Salahs according to his ability, whether standing, sitting, or lying on his side or back. He should observe them in the same order from the first day missed starting with the first Salah missed then the next, and so on. When he finishes the first day, he should start the second day keeping to the order of Salah and so on until he makes up for all the Salahs missed. But if he was not conscious during that period, he is exempted from making up for the missed Salahs.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.