smartavyaḥ satataṁ viṣṇur vismartavyo na jātucit sarve vidhi-niṣedhāḥ syur etayor eva kiṅkarāḥ

smartavyah satatam visnur
vismartavyo na jatucit
sarve vidhi-nisedhah syur
etayor eva kiṅkarah

"Krsna is the origin of Lord Visnu. He should always be remembered and never forgotten at any time. All the rules and prohibitions mentioned in the sastras should be the servants of these two principles." This is a quotation from Padma Purana in the portion called Brhat-sahasra-nama-stotra.

Pratah-krtya means that one should evacuate regularly and then cleanse himself by taking a bath. One has to gargle (acamana) and brush his teeth (danta-dhavana). He should do this either with twigs or a toothbrush-whatever is available. This will purify the mouth. Then one should take his bath. Actually householders and vanaprasthas should bathe two times a day (pratar-madhyahnayoh snanam vanaprastha-grhasthayoh). A sannyasi should bathe three times daily, and a brahmacari may take only one bath a day. Whenever one is not able to bathe in water, he can bathe by chanting the Hare Krsna mantra. One also has to perform his sandhyadi-vandana-that is, one has to chant his Gayatri mantra three times daily-morning, noon and evening.