Nagula Chavithi Pooja Vidhanam is explained here with Mantras, slokas, etc.. Nagula Chavithi is observed in Karthika Masam as per Telugu calendar. In 2017, Nagula Chavithi date is October 24.
Here is Nagula Chavithi puja procedure & Mantras to chant during this vrat.
This vrat is mentioned as ‘Naganamanandakari’ in our ancient scriptures as it is the happiest day (tithi) for Naga Devatas (Serpent Gods).
In the morning, prior to the beginning of Nagula Chavithi puja, recite this mantra as many times as possible:
Anantham Vasukim Sesham Padmanabham Cha Kambalam
Shankhaphalam Dhartharashtram Thakshakam Kaliyam Thatha
Ethani Nava Namani Naganaam Cha Mahatmanam
Sayamkale Pathennityam Pratah Kale Viseshatha
Thasmai Vishabhayam Naasthi Sarvatra Vijayee Bhaveth
After chanting this mantra, perform Sankalpam for Vratha, Upavas and Puja. Offer bath to the Serpent God (Nagadevta idol) and offer milk to the God as Naivedya. It is performed either in Naga devta temple or at home. After Ksheerabhisheka perform Jalabhisheka (bath with water). Offer Shodashopachar puja with gandha (chandan), flowers, dhupa, deepa, naivedya, etc. Now, chant the below mantra..
Sarva Naagam Preeyatham May Ye Kechith Pruthwithale
Ye Cha Helimarichistha Yenarthe Divi Samsthitha
Ye Nadeeshu Mahanaaga Ye Saraswati Gaamina
Ye Cha Vaapee Thadaageshu Theshu Sarveshu Vai Namah
Now, chant Naga Gayatri Mantram for as many times as possible
Om Nagakulaya Vidmahe Vishadantaya Dheemahi Thanno Sarpa Prachodayath
It concludes the puja. Distribute the Prashad among all other devotees.