Firstly: the Permissible Actions in As-Salah
1- Walking in Salah due to some need which occurs; with the condition that one does not turn away from the Qiblah, like opening a door which is in the direction of the Qiblah.
2- Carrying children during the Salah.
3- Killing a scorpion or a snake during the Salah.
4- Looking to the right or left for some need, while in Salah.
5- Crying in Salah .
6- Saying Subhan-Allah for men, and clapping for women.
7- Helping the imam who has forgotten the Ayah.
8- Pointing with the finger or hand to indicate that you are in prayer to someone who enters and greets you. (Making ones palm face down and the back of the hand face up.)
9- Using some sort of hand signal to indicate something to someone due to there being a serious need for the one praying to alert them to something.
10- Praising Allah, if one sees that which calls for it.
11- Spitting to ones left.
12- Preventing a person from passing in front of you while you are praying.
Secondly: The Disliked Actions in As-Salah
1- Entering the prayer while one is distracted; having their thoughts elsewhere or being in a state which distracts himself or his imam; like holding back urine, wind or defecation, being in a state of hunger or thirst, when food which he wishes to eat is present, or looking at that which distracts him from Salah.
2- Useless movements; Meaning doing that which is contrary to being tranquil and concentrating in Salah.
Ex: Moving without a need, playing with ones beard, clothing or watch, cracking ones knuckles, or putting the fingers of one hand in between those of the other hand,
3- Looking with ones face left or right without a need; with the condition that the body does not turn away from the Qiblah; otherwise the Salah would be invalidated.
4- Putting ones hands on ones hips; since it is the action of the Jews.
5- Covering ones mouth and nose in prayer.
6- Rolling up ones garment, sleeves or the likes.
7- Tying ones hair back, gathering it, or braiding it for men; as this would resemble a man whose hands are tied up behind his back. This is because when he prostrates, his hair would not prostrate with him.
8- Spitting in the direction of the Qiblah or to ones right side.
9- Looking up at the sky.
10- Closing one’s eyes, except for a need.
11- Stretching ones arms flat on the ground when in prostration.
Thirdly: The Invalidators of As-Salah
1- Performing something which breaks one of the conditions of Salah; like intentionally exposing the parts of the body that should be covered, turning the whole body away from the Qiblah, intending to stop the prayer when one is in the middle of it, or the occurrence of that which breaks ones state of ritual purity.
2- Intentionally intending to leave an integral or obligatory aspect of Salah .
3- Moving a lot if the movements are not part of those of the Salah, and there is no need for them; like unnecessary walking.
4- Laughing out loud.
5- Intentionally speaking.
6- Intentionally eating or drinking.
7- Intentionally adding a Rak’ah or integral.
8- Intentionally making the final Salam before the imam.