It is narrated from Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) that he saw a man moving the pebbles with his hands while he was praying. When he finished the prayer with the salam, he said to him: "Do not play with the pebbles in the prayer, for this is from Satan; do as the Messenger of Allah (peace and blessings be upon him) used to do." He asked: How did he use to do it? Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) said: "He (peace and blessings be upon him) would place his right hand on his (right) thigh, point with the finger next to the thumb towards the qiblah, and keep looking at it." Then he said: "I saw the Messenger of Allah (peace and blessings be upon him) doing it like this."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2789