ENOfficial
‘Abdallah b. az-Zubair said that when God’s Messenger sat making supplication he placed his right hand on his right thigh and his left hand on his left thigh, pointed with his forefinger, placed his thumb on his middle finger, and covered his knee with the palm of his left hand. Muslim transmitted it.
Source: sunnah.com
Other translations
Arabic
وَعَن عبد الله بن الزبير قَالَ: كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ إِذَا قَعَدَ يَدْعُو وَضَعَ يَدَهُ الْيُمْنَى عَلَى فَخِذِهِ الْيُمْنَى وَيَدَهُ الْيُسْرَى عَلَى فَخِذِهِ الْيُسْرَى وَأَشَارَ بِأُصْبُعِهِ السَّبَّابَةِ وَوَضَعَ إِبْهَامَهُ عَلَى أُصْبُعِهِ الْوُسْطَى ويلقم كَفه الْيُسْرَى ركبته. رَوَاهُ مُسلم
sunnah.com