Abdullah bin Shaqiq (may Allah have mercy on him) said: I asked Sayyidah Aishah (may Allah be pleased with her) about the voluntary prayer of the Prophet (peace and blessings be upon him), and she said: He (peace and blessings be upon him) used to pray four rak'ahs before Zuhr in my house, then he (peace and blessings be upon him) would go out and lead the people in prayer, then, having finished the prayer, he would return to my house and pray two rak'ahs. He (peace and blessings be upon him) would lead the people in the Maghrib prayer and then come back to my house and offer two rak'ahs. Then he would lead them in the Isha prayer, come to my house and again offer two rak'ahs. His (peace and blessings be upon him) night prayer numbered nine rak'ahs, witr included among them. He (peace and blessings be upon him) would spend the rest of the night praying, standing, and at times sitting. When he (peace and blessings be upon him) prayed standing, he made the bowing and prostration from standing; when he recited sitting, he also made the bowing and prostration sitting. And when dawn broke, he (peace and blessings be upon him) would offer two rak'ahs and then go and lead the people in prayer.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4476