SB 4.12.49-50

paurṇamāsyāṁ sinīvālyāṁ
 dvādaśyāṁ śravaṇe ’thavā
dina-kṣaye vyatīpāte
 saṅkrame ’rkadine ’pi vā
śrāvayec chraddadhānānāṁ
 tīrtha-pāda-padāśrayaḥ
necchaṁs tatrātmanātmānaṁ
 santuṣṭa iti sidhyati
Synonyms: 
paurṇamāsyām — on the full-moon day; sinīvālyām — on the dark-moon day; dvādaśyām — on the day after Ekādaśī; śravaṇe — during the Śravaṇa star’s appearance; athavā — or; dina-kṣaye — at the end of the tithi; vyatīpāte — a particular day of the name; saṅkrame — at the end of the month; arkadine — on Sunday; api — also; — or; śrāvayet — one should recite; śraddadhānānām — to a receptive audience; tīrtha-pāda — of the Supreme Personality of Godhead; pada-āśrayaḥ — taken shelter of the lotus feet; na icchan — without desiring remuneration; tatra — there; ātmanā — by the self; ātmānam — the mind; santuṣṭaḥ — pacified; iti — thus; sidhyati — becomes perfect.
Translation: 
Persons who have completely taken shelter of the lotus feet of the Lord should recite this narration of Dhruva Mahārāja without taking remuneration. Specifically, recitation is recommended on the full-moon or dark-moon day, on the day after Ekādaśī, on the appearance of the Śravaṇa star, at the end of a particular tithi, or the occasion of Vyatīpāta, at the end of the month, or on Sunday. Such recitation should of course be performed before a favorable audience. When recitation is performed this way, without professional motive, the reciter and audience become perfect.
Purport: 

Professional reciters may ask money to extinguish the blazing fire within their bellies, but they cannot make any spiritual improvement or become perfect. It is therefore strictly forbidden to recite Śrīmad-Bhāgavatam as a profession to earn a livelihood. Only one who is completely surrendered at the lotus feet of the Supreme Personality of Godhead, depending fully on Him for personal maintenance or even for maintenance of his family, can attain perfection by recitation of Śrīmad-Bhāgavatam, which is full of narrations of the pastimes of the Lord and His devotees. The process can be summarized as follows: the audience must be faithfully receptive to the Bhāgavata message, and the reciter should completely depend on the Supreme Personality of Godhead. Bhāgavata recitation must not be a business. If done in the right way, not only does the reciter achieve perfect satisfaction, but the Lord also is very satisfied with the reciter and the audience, and thus both are liberated from material bondage simply by the process of hearing.