Saying Bismillah Is Recommended Before Eating:
The Prophet (saw) said,
“Say Bismillah, eat with your right hand and eat what is in front of you.”
[Bukhari 7/88, Muslim 2/207, Ahmad 17/92, Muwatta Malik 10/32 and Ibn Majah 1/557]
Saying Bismillah Is Recommended When Drinking Water:
Ibn Abbas (ra) reported that the Messenger of Allah (saw) said,
“Do not drink in one gulp like a camel, but in two or three [Gulps]. Mention the Name of Allah when you start drinking and praise Him after you have finished Drinking.”
[Fath al-Bari 12/197 and Al-Trimidhi]
Saying Bismillah Is Recommended At The Beginning Of Ablution:
The Prophet (saw) said,
“Make Wudu [Ablution] in the name of Allah”
[An-Nasai 1/11 and Ibn Khuzaimah 1/84]
Saying Bismillah Is Recommended When Entering The House:
Jabir (ra) said: I heard the Messenger of Allah (saw) saying,
“If a person mentions the Name of Allah upon entering his house or eating, Satan says, addressing his followers: `You will find no where to spend the night and no dinner.’ But if he enters without mentioning the Name of Allah, Satan says [To his followers]; `You have found [A place] to spend the night in, and if he does not mention the Name of Allah at the time of eating, Satan says: `You have found [A place] to spend the night in as well as food.”
[Sahih Muslim 2/206]
Saying Bismillah Is Recommended When Leaving The House:
The Messenger Of Allah (saw) said,
“If anyone of you when leaving the house says In the name of Allah, I trust in Allah, there is no power and might except from Allah. Your needs shall be fulfilled, you shall be saved from difficulties and hardships. Shaitaan hearing these words leaves him.”
[Al-Trimidhi 2/493]