Jami` at-Tirmidhi Book 43, Hadith 15
that when the Prophet (ﷺ) would sneeze, he would cover his face with his hand or with his garment, and muffle the sound with it.
from his mother, from her father, who said: "The Messenger of Allah (ﷺ) said: 'Reply three times to the sneezing person. If he (sneezes) more, then if you wish reply and if you do not then do not.'"
that the Messenger of Allah (ﷺ) said: "The sneeze is from Allah and the yawn is from Ash-Shaitan. So when one of you yawns let him cover his mouth with his hand. For when he says 'Ah, Ah' Ash-Shaitan laughs from inside his opening."