Which scripture tells us about the rules and procedures for doing Saraswati upasana?
In Hinduism Devi Saraswati is goddess of speech , learning ,music ,art. She is depected as sitting on a white swan and holding a Vina (stringed instrument) in her hands. She clad in white clothes and a book in her other hand , which are Vedas. According to Pancharatra texts she is one of the twenty-four emanations of Lakshmi accompanying Narayana. i.e. She is conceived as Shakti related to Vishnu.
The method of worship of Devi Saraswati is described in detail in Devi-Bhagavata Purana - Book 9 - Chapter 4 - On the hymn, worship and Kavaca of Sarasvatī Devī. This mode of worship of devi Saraswati is told by Narayana to Narada.
32-59. Nārāyaṇa said :-- O Nārada! I am now stating the method of worship of the Devī Sarasvatī, the Mother of the Worlds, according to Kaṇva Śākhā of the Yajurveda. Hear. On the day previous to the fifth day of the bright fortnight of the month of Māgh or the day of commencement of education, the devotee should control his senses, concentrate his mind and take his bath. Then he is to perform his daily duties and install the jar (Ghaṭa) with devotion and according to the Mantras of the Kaṇva Śākhā or the Tantra, as the case may be. He is to worship first on that Ghata (jar) Gaṇapati (Ganeśa), then meditate the Devī Sarasvatī as described below, invoke Her and again read the Dhyān and then worship with Soḍaśopacāra (sixteen good articles offered in the worship). O Good One! Now I am speaking, according to my knowledge, about the offerings as ordained in the Vedas or Tantras. Hear. Fresh butter, curd, thickened milk, rice freed from the husk by frying, sweetmeats (Til Laddu) prepared of Til, sugar cane, sugarcane juice, nice Guḍ (molasses), honey, svastik, sugar, rice (not broken) out of white Dhān, cipiṭak of table rice (Ālo cāl), white Modak, Harbiṣyānna prepared of boiled rice with clarified butter and salt, Piṣṭaka of jaoā or wheaten flour, Paramānna with ghee, nectar like sweetmeats, cocoanut, cocoanut water, Svastik Piṣṭaka, Svastik and ripe plantain Piṣṭaka, Kaseru (root), Mūlā, ginger, ripe plantains, excellent Bel fruit, the jujube fruit, and other appropriate white purified fruits of the season and peculiar to the place are to be offered in the Poojā. O Nārada! White flowers of good scent, white sandalpaste of good scent, new white clothes, nice conchshell, nice garlands of white flowers, nice white necklaces, and beautiful ornament are to be given to the Devī. I say now the Dhyānam sweet to hear, of the Devī Sarasvatī according to the Vedas, capable to remove errors! Hear. I hereby bow down to the Devī Sarasvatī, of a white colour, of a smiling countenance and exceedingly beautiful, the lustre of whose body overpowers that of the ten millions of Moons, whose garment is purified by fire, in whose hands there are Vīṇā and books, who is decorated with new excellent ornaments of jewels and pearls and whom Brahmā, Viṣṇu, Maheśvara and the other Devas, Munis, Manus and men constantly worship. Thus meditating the Devī, the intelligent persons should offer all articles, after pronouncing the root Mantra. Then he is to hymn and hold Kavaca and make Sāṣṭāṅga praṇāms before the Devī. O Muni! Those whose Devī Sarasvatī is the presiding Deity, are not to be spoken of at all (i.e., they will naturally do all these things and with a greater fervour). Besides all should worship the Devī Sarasvatī on the day of commencement of education and every year on the Śūkla Pañcamī day of the month of Māgh. The eight-lettered Mantra, as mentioned in the Vedas is the root Mantra of Sarasvatī. (Aim Klīm Sarasvatyai namaḥ). Or the Mantra to which each worshipper is initiated is his Mūlmantra (not Mantra). Or uttering the Mantra “Śrīm Hrīm Sarasvatyai Svāhā” one is to offer everything to the Devī Sarasvatī. This Mantra is the Kalpa Vrikṣa (i. e., the tree which yields all desires). Nārāyaṇa, the ocean of mercy, gave in ancient times, this very Mantra to Vālmikī in the holy land Bhārata Varṣa on the banks of the Ganges; next Bhrīgu gave this Mantra on the occasion of solar eclipse to Maharṣi Sukrācarya on the Puṣkara Tīrtha; Mārīca gave to Brihaspati on a lunar eclipse; Brahmā gave to Bhrīgu in the Vadarikā Āśrama; Jaratkarā gave to Āstika on the shore of the Kṣiroda ocean; Bibhānḍaka gave this to the intelligent Ṛṣyasriṅga on the Sumeru mountain, Śiva gave this to Kaṇāda and Gotama, Sūrya gave to Yājñavalkya and Kātyāyana, Ananta Deva gave to Pāṇini, to the intelligent Bhāradvāja and to Śākaṭāyana in Bali’s assembly in the Pātāla. If this Mantra be repeated four lakhs of times, all men attain success. And when they become Siddhas with this Mantra, they become powerful like Brihaspati.
In brief - The worship of Devi Saraswati should be performed as mentioned in Vedas/Tantaras with Shodasha Upachara i.e.with sixteen good articles offered in the worship.
Some of the food iteams offered to goddess are Ghee , Curd ,seasom laddu , white Modak , cocoanut ,suger honey , Jaggery, bel fruit , various iteams of cook rice (Sweet , sour) . etc. as naivaidya .
For Pooja purpose white flowers , white clothes, white sandal paste ,scent , conchshell, garland of white flowers and ornaments can be offered to please the Goddess.
Worshipper should perform Dhyana (meditation ) of Saraswati and offere all the articles to her. He should utter the eight letter Saraswati Mool Mantra " “Śrīm Hrīm Sarasvatyai Svāhā” and "Aim Klīm Sarasvatyai namaḥ " only if he is initiated by his guru.
As mentioned in Devi Bhgvata Purana the goddess should be worshipped by Shodashopachar Puja which includes.
1) Avahana -Calling for goddess to come to puja 2) Asana - Providing seat for the deity to sit. 3) Padya - washing feet of the goddess with water.
4 ) Arghya -Offering water to goddess 5) Achamana - Providing water for the goddess for drinking 6) Abhisheka - for bathing purpose , Offer continuous water offerings to the deity.
7 ) Vastra 8) UpaVastra- Offering a garment .9 )Aroma -Offering Chandana as perfume to Goddess.
10) Pushpa - Offering flowers and flowers to God. 11) Dhoop - Offering incense made by incense-natural aroma. 12) Deep - Offering a lamp to the goddess and incense to the taja part of the deity.
13) Naivaidya- Offering prepared food items as prescribed in pooja vidhi to goddes.14 )Pradakshina - completing a circle around goddess idol. 15) Namaskar - Greetings to the Goddess. 16 ) Mantrapushpanjali- Offering godliness and flowers to God as a symbol of anything short of mantra-worship.
So the above is the way one can perform an Upasana or Pooja of Devi Saraswat. Also we can sing Aarati , can chants various Devi Saraswati mantras etc. during the upasana puja and can meditate on her as a supreme Goddess.