It is recommended to recite the Dhuhr and Asr Prayers under the open sky
Two unit (rakaah) prayer After obligatory prayers, it is recommended to offer a two unit prayer reciting Surah al-Fatihah and Surah al-Tawhid in the first unit and Surah al-Fatihah and Surah al-Kafirun in the second.
Two unit prayer under the open sky After the 'Asr Prayer and before the reciting the supplications of 'Arafah' Day
offer another 2 unit prayer (like fajr prayers) under the open sky, confessing one's sins before Allah (swt). One who offers this prayer will be granted the reward of being present on Mount `Arafah and having all sins forgiven.