upon finishing prayer he pbuh would ask allah for forgiveness three times and then say:
"allaahumma antas-salaamu wa minkas-salaamu, tabaarakta ya dhal-jalaali wal- ikraam." (o allah, you are peace and from you comes peace. blessed are you, o owner of majesty and honour.”he pbuh remained facing the qiblah only long enough to complete this supplication. then he would immediately turn to face the worshippers, either to the left or to the right.
after concluding the fajr prayer, he stayed in his place of prayer until sunrise.
he pbuh also used to say after every obligatory prayer:
"la ilaaha ill-allaahu wahdahu la shareeka lahu, lahu-mulku wa lahul-hamdu wa huwa `ala kulli shay'in qadeer. allaahumma la maani`a lima a`tayta, wa la mu`tiya lima mana`ta, wa la yanfa`u dhal-jaddi minkal-jadd.”
(there is no god but allah, alone, having no partner. his is sovereignty and to him is all praise and he pbuh is over all things competent. o allah, there is no preventer of what you grant and no granter of what you prevent, and no means will benefit a man of means against you.)
“la hawla wa la quwwata illa billaah. la ilaaha il-allaahu, wa la na`budu illa iyyaah. lahun-ni`matu wa lahul-fadhlu wa lahuth-thanaa'ul-hasan. la ilaaha ill-allaahu, mukhliseena lahud-deena wa lau karihal-kaafiroon."
(there is no might or power except through allah. there is no god but allah and we worship none but him. all blessing is his and all favour, and to him is due the best praise. there is no god but allah. we are sincere in religion to him alone, even if the disbelievers dislike it.)
he pbuh urged his followers to say after the obligatory prayer: "subhan allah" (glory be to allah) thirty three times, "al-hamdulillah" (praise be to allah) thirty three times, "allahu akbar" (allah is most great), thirty three times and complete one hundred by saying,
“la ilaha 'ill-allaahu wahdahu la shareeka lahu, lahul-mulku wa lahul-hamdu wa huwa `ala kulli shay'in qadeer."
(there is no god but allah, alone, having no partner. his is sovereignty and to him is all praise and he is over all things competent.)
 al-bukhari and muslim.