Wa alaykum salaam wa rahmatullahi wa barakatuhu
There is no established form of warning which was transmitted in the Sunnah where the Prophet (peace be upon him) said, " Verily in these houses there live aged (snakes), so when you see one of them," and another narration he said, "inform them."
As for what was transmitted by Abu Dawud (5260) that the Prophet (peace be upon him) was asked about snakes, and he said, " When you see one of them in your dwelling, say: I adjure you by the covenant which Noah made with you, and I adjure you by the covenant which Solomon made with you not to harm us. Then if they come back, kill them," that is a weak hadeeth according to the scholars because its chain of narrators does not reach the Prophet (peace be upon him). Moreover, one the narrators, Muhammad ibn Abi Layla was a weak narrator. However, if a person utters these words, nothing is wrong, because they consist of a warning. So this warning can be of any form which achieves the objective. It has been transmitted that Imam Malik said that it is sufficient to warn the snake by saying, "I adjure you by Allah, and the day of Judgment that you should not appear to us, nor should you harm us." It seems that Imam Malik took these words from the hadeeth of Abu Sa'id al-Khudri (may Allah be pleased with him).
And Allah knows best.