How to offer namaz prayer?

It is related by Hadhrat Abu hurairah (R.A.) that (once) the Apostle of Allah (Sallallaho alaiho wasallam) was sitting to one side in the mosque that a man came in and offered his Namaz (Prayer). Afterwards, he came to the holy Prophet (SAW) and paid his respects to him. The Holy Prophet (SAW) returned the salutation and remarked: "Go and offer the Namaz (Prayer) again. You have not said it properly." He went back and said the prayers again and returned to the Holy Prophet (SAW), and paid his respects. The Holy Prophet (SAW), returning the salutation, once again remarked: "Go and offer the Namaz (Prayer) again. You have not said it properly". After offering Namaz (Prayer) for the third (and the fourth) time, the man said to the Holy Prophet (SAW): "Sir, tell me how to offer Namaz (Prayer)". The Holy Prophet (SAW) replied: "When you decide to offer Namaz (Prayer), first perform Wadhu throughly and well, then turn to Qibla, then begin the Namaz (Prayer), after uttering Takbir-i-Tahrima. After it recite some part of the Holy Qur’aan which you know by heart and can recite easily. (In other Traditions relating to the same incident it is stated that the Apostle of Allah (SAW) told the questioner, specifically, to recite Surah-i-Fateha and whatever he liked, in addition to it). Then after the recital, perform Ruku till you are still and at ease in Ruku. Then, arise from Ruku till you stand erect. Then, perform the Sajadah till you are still and at ease in Sajadah. Then arise till you sit up comfortably. (According to another narrator, the Holy Prophet (SAW), instead of it, said: "Then arise till you stand erect). Then, do like that throughout the Namaz (Prayer) (i.e., in every Ruku, Sujud, Qauma and Jalsa in a calm and collected manner)." (Bukhari and Muslim)

The incident mentioned above related to Hadhrat Khallad bin Rafay (RA), the brother of the well-known Sahabi, Hadhrat Rifa’ah bin Rafay (RA). According to Nassai, he had offered up two Raka’ah of Namaz (Prayer) in the Holy Prophet’s (SAW) mosque but some other commentators suggest that these Raka’ah were of Tahiyyat-ul-Masjid which Hadhrat Khallad (RA), had said rather hurriedly, and upon it, he was reproached by the Holy Prophet (SAW) and told to offer them up again.

It shows that the Holy Prophet (SAW) did not plainly tell Hadhrat Khallad bin Rafay (RA), at the first time, what was wrong with his Namaz (Prayer) and how it was to be said correctly but at the third or fourth time, and, then, at his own request. It was, probably, for the simple reason that a lesson imparted in such a manner suffices for a lifetime and gets talked about among others as well.

The paractical teaching imparted in the above Tradition is that Namaz (Prayer) should be offered up in a calm and composed manner and if it is offered hurriedly and wiithout making the necessary pauses and carrying out the various acts properly it be as good as unsaid.

Source: http://www.easyislam.com/how_to_offer_namaz_prayer.asp