It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both): Sayyiduna Ali (may Allah be pleased with him) came to me; he had relieved himself, then he called for water. We brought him water in a vessel and placed it before him. Sayyiduna Ali (may Allah be pleased with him) said: "O Ibn Abbas! Shall I not show you how the Messenger of Allah (peace and blessings be upon him) used to perform ablution?" I said: "Certainly!" So he tilted the vessel onto his hand and washed his hands, then put his right hand into the vessel and with that hand poured water onto the other hand, then washed his palms, then rinsed his mouth and blew his nose. Then he put both his hands into the vessel together, took a handful (of water) with both hands and struck his face with it, then put his thumbs into the front part of the ears, then did the same a second and a third time. Then he took a handful of water with his right hand and poured it onto his forehead, then he left that water, and the water was flowing down his forehead.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 245