Alqamah bin Wa'il and a freed slave of theirs both narrated from Alqamah's father, Sayyiduna Wa'il (may Allah be pleased with him), that he saw the Prophet (peace and blessings be upon him) saying the takbir when beginning the prayer. Abu Uthman (a narrator in the chain) says that Hammam also described that he raised both hands up to the level of his ears, then wrapped his hands in his garment and placed the right hand over the left hand. Then, when he intended to bow, he brought his hands out of the cloak and said the takbir while raising his hands. Then when he said 'Sami' Allahu liman hamidah' (Allah hears the one who praises Him), he raised his hands as well. Then, when he prostrated, he prostrated between his two palms.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2515