Jamiat Tirmidhi: Hadith 48

"I saw Ali performing Wudu. He washed his hands until he cleaned them, then he rinsed out his mouth three times, sniffed water into his nose and blew it out three times, washed his face three times, and his forearms three times. He wiped his head once, then he washed his feet up to the ankles. Then he stood up, taking what was left over from his purification (water) and drank it while he was standing. Then he said, 'I wanted to show you how Allah's Messenger purified himself.'"