Belpatra- Bel Patra or the Bilva leaves are a favorite of Lord Shiva. Bilva leaves represent the Trinity- Brahma, Vishnu, and Mahesha. The three leaves are also believed to be the three eyes of Lord Shiva. Bilva leaves to balance the three humors or the doshas- Vata, Pitta, and Kapha.
Raw milk and water- Milk is the symbol of purity while water is essential for sustenance by all creatures. Both these fluids are eternal and also signify the first human diet. Offering milk and water to Lord Shiva has a soothing effect on the nervous system.
Panchamrit- Panchamrit is a mixture of five liquids- milk, curd, honey, sugar, and ghee or clarified butter. These are the five ambrosial ingredients and represent the essential essences of the human body. Offering the Panchamrit on the Shivlinga will exert an invigorating effect on the entire body.
Gangajal- Ganga is the heavenly river flowing from the matted locks of Lord Shiva. Her waters symbolize purity and are enough to wash away the sins of one's numerous lifetimes. Her descent on earth speaks of the powers of penance (since She is the result of King Bhagiratha's severe penance) and the innumerable possibilities that mankind can unleash.
Bhasma or the Ash- Bhasma or ashes are extremely dear to Lord Shiva. From nothing we come and to nothing we go. Ashes represent the dissolution of Ego - the prime principle of destruction of knowledge and wisdom in man.
Datura- Datura fruit and flowers are both Lord Shiva's favorite. Offering the flowers and fruits of Datura to Lord Shiva represents the eternal bliss that one gets in the higher states of meditation.
Besides the above ingredients; sandal paste, camphor, incense sticks, ghee lamp, unbroken rice, rose water and perfumes are also offered to Lord Shiva
. However, tulsi, vermillion and kewda flowers are not included in His worship.
Rudra is the perfect manifestation of Shiv. Doing Rudrabhishek has various benefits-