Devibhagavatapurana 12.7.42

12.7.42

śrīnārāyaṇa uvāca |
tataḥ svavāmabhāgāgre ṣaṭkoṇopari vartulam |
caturasrayutaṃ samyaṅmadhye maṇḍalamālikhet ||

O Nârada! Now, on one’s left side, erect an hectagon; inside it a circular figure; inside this again a square and then draw within that square a triangle and over it show the S’ankha Mudrâ. After finishing the Pûjâ of the Six Deities at the six corners of the hectagon, Fire, etc., take the tripod of the S’ankha (conch-shell) and sprinkling it with Phat mantra, place it within the triangle. Utter, then, the Mantra “Mam Vahniman dalâya Das’a Kalâtmane Amuka Devyâ Arghyapâtrasthânâya namah” and thus worshipping the S’ânkhya vessel place it within the mandala. Then worship in the S’ankha pâtra, the ten Kalâs of Fire, beginning from the East, then south-east and so on. Sprinkle the S’ankha, conchshell, with the Mûla Mantra and meditating on it, place the S’ankha (conch shell) on the tripod. Repeating the mantra “Am Sûrya mandalâya Dvadas’akalâtmane Amukodevyâ Arghyapâtrâya namah” worship in the Arghyapâtra S’ankha, sprinkle water in the S’ankha with the Mantra “Sam S’ankhya namah.” Worship in due order the twelve Kalâs of the Sun Tapinî, Tâpinî, Dhûmrâ, etc., utter the fifty syllables of the Mâtrikâ in an inverse order (i.e., beginning, see the Sâradâ Tilaka, with Ksam, Ham, Sam, Sam, S’am, etc.,) and repeating the Mûla Mantra also in an inverse order, fill the S’ankha, three-fourths, with water. Next perform in it the Nyâsa of Chandrakalâ and uttering the Mantra “Um Soma mandalâya Sodas’akalâtmane Amukademtâyâ Arghyâ-mritâya namah,” worship in this conchshell. Next with Ankus’a mudrâ, invoke all the tîrthas there, repeating the Mantra “Gange Cha Yamune chaiva, etc.,” and repeat eight times the Mûla Mantra (the basic Mantra). Then perform the S’adamga Nyâsa in the water and with the Mantra “Hridâ namah, etc.,” worship and, repeating eight times the Mûla Mantra, cover it with Matsyamundrâ. Next place on the right side of the S’ankha, the Proksanî Pâtra (the Kos’â vessel from which water is taken for sprinkling) and put a little water in it. By this water sprinkle and purify all the articles of worship as well as one’s own body and consider one’s Âtman as pure and holy.