Is it permissible to vary the methods of worship, such as varying the raising of hands in the opening Takbir (Takbirat Al-Ihram), the opening supplications (Du'a Al-Istiftah), the grasping of hands, and other actions firmly established from the Prophet, may Allah's prayers and peace be upon him?

Varying acts of worship is a good and desirable practice for reviving the Sunnah. The opening supplication (Du'a al-Istiftah) is a Sunnah, and it has been reported in many forms. The best approach is to recite all the authentically reported forms by varying them. Raising the hands at the opening takbir (Takbirat al-Ihram) is a Sunnah, and there are two authentically reported methods for it: raising them level with the shoulders or level with the ears, and both are Sunnah. Placing the right hand over the left is an authentically established Sunnah, and narrations differ regarding its placement: on the chest or below the navel, and both conform to the Sunnah.