Eternal Reality,

 Manasthe padhabjhenivasathu vacha sthothra phanithou Karou chabhyarchyam sruthirapi kadha karnanavidhou Thava dhyane budhir nayana yugalam moorthi vibhave Para grandhan kairvaaparamashiva janee para matha

Meaning: - Let the mind  dwell on your two lotuses like feet, Let my words dwell on your praise, Let my two hands dwell on your worship, Let my ears dwell on hearing your holy stories, Let my mind dwell meditating on you, Let my two eyes dwell on your beauty, And after this I do not find any use, Of other great books tome, Oh supreme God?   By Sri Adi Sankara Bhagawatpada. (SivanandhaLahari)
Lord Siva is the supreme Reality. He is eternal, formless, independent, omnipresent, one without a second, beginning less, causeless, taint less self-existent, ever free, ever pure. He is not limited by time. He is infinite bliss and immeasurable brain power.
Lord Siva pervades the whole world by his Sakti.  Sakti is conscious energy of Lord Siva. She is the very body of Lord Siva to the world. Imagine ourselves making a pot what things we need…  The potter is the first cause. The stick and the wheel are the instrumental causes. The clay is the material cause of the pot. Similarly, Lord Siva is the first cause of the world. Sakti is the instrumental cause. Maya is the material cause.
Adi Sankara, in his interpretation of the name Siva, the 27th and 600th nama of Vishnu Sahasranamam,interprets Siva to have multiple meanings: "The Pure One", or “the One who is not affected by three Guna’s of Prakrti (Satva, Rajasa, and Tamasa)" or "the One who purifies everyone by the very word of his name."
Swami Chinmayananda, in his translation of Vishnu sahasranamam, further elaborates on that verse: Siva means "the One who is eternally pure" or "the One who can never have any contamination of the imperfection of Rajasa and Tamasa”. Siva is considered a God who has no Aadi or Antyam i.e., no beginning and no end.
Symbols:
1. The fact of waxing and waning of the moon symbolizes the time cycle through which creation evolves from the beginning to the end. Since the Lord is the Eternal Reality, He is beyond time. Thus, the crescent moon is only one of his ornaments. The fixing of the crescent moon in his head indicates that He has controlled the mind perfectly. This means he is giver of peace (Santham)
2. Lord Siva smears his body with ashes (bhasbam). It is said ashes represent the final reality that a human being will face - the end of all material existence
3. Sacred Ganges: Bearer of Ganga. Ganges River flows from the matted hair of Siva. The Ganges one of the major rivers of the country is said to have made her abode in Siva's hair. The flow of the Ganges also represents the nectar of immortality. This is the reason Lord is called Gangadharan
4. Tiger skin: He is often shown seated upon a tiger skin; an honor reserved for the most accomplished of ascetics, the Brahma rishis. Tiger represents lust. His sitting on the tiger’s skin indicates that he has conquered lust; He has no pleasure or pain
5. Serpents: "NagendraHaaram". Siva is wearing of serpents on his neck symbolizes wisdom, eternity and represent Kundalini Sakthi is under his control…
6. Deer: His holding deer on one hand indicates that He has removed the sanchalams(confusion) of the mind (i.e., attained maturity and firmness in thought process).
7. Trident: (Trishulam): Siva’s particular weapon is the trident His Trisullam that he is holding in his right hand signifies the three Gunas—Sattva, Rajas and Tamasa. That is the emblem of authority. He rules the world through these three Gunas. (Guna means nature Sattva- Illuminating and Sustaining. Rajasa- creating and moving …. Tamas- Regulating and Dissolving)
8. The Damaru is in his left hand represents the Sabdam (Sound) Brahman. It is reflecting in all languages are formed. Which means all languages are producing from the OMkarappranavam.9. Rishabham (the bull) represents Dharmam. Lord Siva rides on the Bull it is his mount. This signifies that Lord Siva is Dharmamdeva (righteousness).

10. Gaṇas: The Gaṇas are live in Kailash. They are called bhutaganas, on account of their nature. They are often as in prayer to involve all mankind with the lord on behalf of the devotee. Ganesa was chosen as their leader by Siva; hence Ganesa is heading Ganas so he is called Gana+isha =Genesha or Gana+pati, Ganapathi. The lord of the Ganas"

 11. Abode: Mount Kailash is in the Himalayas. It is Lord Siva’s enduring abode and it is resembling as a Lingam in the center of the universe.

Worshiping Siva in the form of a Lingam is a great value.  Siva means auspiciousness, and lingam means a sign or a great symbol. Hence, the Siva lingam is regarded as a “symbol of the Supreme Lord of the universe who is all-auspiciousness.  It is the same god creates the universe, sustains it and absorbs the universe; the Shivalingam is symbolizes the Lord himself.

Pañchabrahma Upanishad says: One should know about the incredible world which is of a fivefold character. The eternal truth of Siva is of the character of the fivefold Brahman, contained with five letters. five elements called panchaboothams, that is Water, earth, fire, sky, air.  He has five Sabas. pancha brhama kshetrams and he is a family-oriented god.The Lord is to mark as a characteristic both an ascetic yogi and as a householder, he has a consort, Parvati, and two sons, Ganesar and Subramaniam.

It is also represented as four Vedas Rig, Yajur, Sama, and Atharva. (Siva, Sakthi, Ganesar, and Subramanyam)
The Lord shows to the world as yogi, even though family oriented he should be unattached with any bondage and he should be like a Swans. Swans always in the water but their claws will not attract wet and another nature of the swans if you mix water with the milk, it will separate water from the milk and drink pure milk, alike the people should aloof from the evil perceive only the true knowledge. Lotus leaves too always in the water but its surface will not get wet. The meaning of this one should not attract with the senses yet should not forget to perform his duties.

There is no rule and condition to worship Lord Siva. One can do    clean Lord's abode, means temples. make garland to the Lord. one can sing the lords praises, lighting lamps in the temple, like this as for as possible help to Lord's Aradhana’s, and fill water for his abishagam.

Other than that yoga is the best to control of the senses and observe on the internal light. Means Understand the true knowledge. But for Yoga, needs initiation from Guru. (Mentioning Yoga means Dyanam (Meditation)) if one feel very difficult to find a spiritual guru, pray Lord as guru he will appear as Sri Dhakshinamoorty, He is a spiritual preceptor with full of grace. He helps the devotees and bestowing with his grace on those who worship him with faith and devotion.
If a person seeks to establish a relationship between himself and Lord Siva, for that he should have the mental approach of the relationship of master and servant which Tirunavukarasar had, or If one think Lord Siva is the father of him he will be as his wish like Tirujnanasambandhar.  If one thinks the friend relationship between Lord Siva and Sundarar, or One wish to pursue as Manikkavasakar the Sanmargam path on Lord Siva yes can.   Whom so ever however observe their devotion on Lord Siva, he too would be the same. There is a devotee becomes one with Siva, like a tree and its root.