The following are prescribed for the observation of Salat(Prayer Etiquettes) :

1- Sincerity

Allah says: “And they were commanded not, but that they should worship Allah, and worship none but Him alone (abstaining from ascribing partners to Him) and perform as-Salat and give Az-Zakah, and this is the right religion.” ( Al-Bayyinah: 5 ).

2- Perfecting ablution

This means being careful to perform ablution perfectly. It was reported on the authority of Abu Hurayrah t, that the Messenger of Allah ﷺ said: “Should I direct you to that with which Allah cleanses away sins and raises ranks?” They replied: “Yes, Oh Messenger of Allah.”

3- Going early to perform the prayer

This means going out early in order to attain the virtues of waiting for Salat.

4- Remembrance of Allah

He (the one who observes Salat ) should remember Allah when leaving the house by saying: “ Bismil-Lahi tawakkaltu ‘ala-l-Lahi wala hawla wala quwwata illa-b-Lah” [ Source: Abu Dawud.]“Allahumma inni a’udhu bika an adhila aw udholu, aw azilla aw uzallu, aw adhlima aw udhlama, aw ajhala aw yujhala ‘alayya.” [Source: Abu Dawud.]

5- Walking calmly and tranquilly to the mosque


This is due to the saying of the Prophet ﷺ : “When you hear the Iqamah (the call to commence the prayer), then walk (to the mosque) to observe the prayer, but (walk) with tranquility (as-sekeenah)[ As-sakinah: Tranquility while walking.] and calmness (al-waqaar)[ Al-waqar: Calmness, lowering one’s gaze and not looking left and right] and do not be hasty. Any part (of the prayer being observed) you meet (that others are praying in congregation) you should pray (with them), and (afterwards) complete what you missed. [ Agreed upon.]

6- While entering and exiting the mosque


While entering the mosque, he says ”A’udhu billahil’atheem, wa biwajhihi alkareem, wa saltanihi alqadeem min ashshaytanirrajeem,” meaning: “I seek refuge in Allah, the Most Great, by His Generous Face and by His Long-lasting Power, from Satan, the accursed.” [ Source: Abu Dawud.]

7- He should not sit down until he observes two rak’ahs (of prayer)


This is due to the saying of the Prophet ﷺ: “When one of you enters the mosque, let him pray two rak ‘ahs before sitting down.” [ Agreed upon.]

8- Abstainence from interlocking the fingers

Taken from the saying of the Prophet ﷺ: “When any of you performs ablution and performs it perfectly, then left to pray, heading to the mosque, he should not interlock his fingers because he is already in a state of prayer.” [ Source: Abu Dawud.]
9- Being occupied with remembrance of Allah


Being occupied with the remembrance of Allah, prayer and recitation of the Qur‘an while waiting for Salat, without disturbing other people who have come to pray.

10- Being humble during Salat

This is because Salat, without humility and devoutness, is like a dead body without a soul.

11- Adhering to the manners of the Prophet ﷺ throughout the prayer

Prayer is a form of worship for which upholding the manners of the Prophet ﷺ is compulsory. So what the Prophet ﷺ did not do or say must not be done or said. This is because the Prophet ﷺ said: “Pray as you saw me pray.” [ Source: Bukhari.]
source: https://www.al-feqh.com/en/some-of-t...ettes-of-salat