Strike your hands on ground once for your face and once again for your both arms before wiping them upto elbow .

Tayammum is a form of ritual purification in Islam which involves striking the ground with one's hands and then wiping one's face and arms up to the elbows. This was practiced by Abdullah ibn Umar who used to do tayammum up to his elbows. The process of tayammum requires striking the ground once for the face and once for both arms before wiping them up to the elbows. This practice is done when water is not available or if an individual cannot use water due to illness or injury. It serves as an alternative way for Muslims to maintain their spiritual purity even when they are unable access water.