Purity: Maintain physical (bathing) and mental purity.
Attire: Wear simple, clean, traditional attire (often white or light-colored Dhoti/Kurta for men, Saree/Salwar for women; avoid black).
Diet: Strict vegetarian diet, avoiding onion, garlic, and sometimes rice, is often required before and during the puja days.
Presence: Physical presence is recommended for maximum benefit, although online options exist. A male member is often required for certain rites like Pind Daan.
Follow all specific instructions from the performing pandit.