It is narrated from Sayyiduna Wa'il al-Hadrami (may Allah be pleased with him) that he prayed with the Messenger of Allah (peace and blessings be upon him). When he recited "nor of those who go astray," he said "Amin" and kept his voice low. Then he placed his right hand on his left hand and placed them on his stomach. When he said "Sami'a Allahu liman hamidah" (Allah hears the one who praises Him), he would say: "O Allah, our Lord, to You belongs all praise." And he would give the salam twice, to the right and to the left.
Hadith Referenceالمعجم الكبير للطبراني / باب الواو / 18330