It wasnarrated that Ibn 'Abbas said:
"The Messenger of Allah (ﷺ)said: 'When you call upon Allah, then do so with the palms of yourhands (upwards). Do not do so with the back of your hands (upwards).And when you finish, then wipe your face with them.'"
English reference: Vol. 1, Book 5, Hadith 1181
Arabic reference: Book 5, Hadith 1237