Our Master was taught how to take ablution and how to perform salat directly from Gabriel. 

One day the Angel Gabriel came to the Rasul of Allah (saw) in the form of a human and hit the ground with his heel whereby a spring of water gushed out. Then Gabriel took ablution and our Master did the same.  Gabriel performed salat and our Master also performed salat with Gabriel. After this Gabriel disappeared…

Later Omar (ra) narrated how our Master took ablution with his words:

“One day the Rasul of Allah came with a tumbler of water and he poured water over his hands and washed them thrice and then put his right hand in the water container and rinsed his mouth, washed his nose by putting water in it and then blowing it out. Then he washed his face and forearms up to the elbows thrice, passed his wet hands over his head and washed his feet up to the ankles thrice. Then he said, ‘If anyone performs ablution like that of mine and offers a two rakah prayer during which he does not think of anything else then his past sins will be forgiven.’ “

In the following hadith our Master explains how to perform salat in detail: 

“When you want to pray, perform wudu (ablution) and do it well, then stand up and face the qiblah. Then say the takbir, then recite, then bow until you are at ease in bowing. Then stand up until you are standing up straight. Then prostrate until you are at ease in prostration, then raise your head until you are at ease in sitting, then prostrate until you are at ease in prostration. Repeat this on every rakat…”

Later our Master said regarding salat:

“When one of you stands to pray, he is indeed conversing with his Rabb. His Rabb is between him and the prayer direction…”

When salat first became compulsory it was in the form of two rakat. Regarding this Aisha (ra) says:

“When Allah enjoined the salat it was two rakat only, both when in residence or on journey. Then the prayers offered on journey remained the same, but the rakat of the prayers for non-travelers were increased (to four).”