On Diwali, Jain practice centers on Mahavira’s Nirvana and the light of true knowledge. Here’s a simple guide:

• Remember Mahavira: Spend time remembering his life, his teachings, and the quest for keval jnana.
• Light the inner lamp: Light a diya or small lamp at home or at the temple as a symbol of spiritual illumination and ahimsa.
• Puja and prayer: Do a short devotion (upa-puja), recite Namokar Mantra or a brief Jain prayer, and read or listen to a small Jain teaching about Mahavira.
• Pratikraman and reflection: If you follow it, perform a brief pratikraman (confession and repentance) and/or a short samayik (quiet, mindful practice).
• Simple worship at home: You may offer flowers, incense, and a small puja to Mahavira and the Tirthankaras; keep the ritual simple and non-violent.
• Study and listening: Read a small passage from a Jain scripture or listen to a short teaching about Mahavira’s wisdom.
• Charity and kindness: Share something with others, help those in need, and practice dana (generosity).
• Avoid harm and noise: Refrain from activities that cause harm to living beings; avoid loud firecrackers and violence.
• Calendar note for 2025: The main Jain Diwali day is observed on Kartik Amavasya, commonly on October 20, 2025. Some calendars note a two-day Amavasya span (into October 21). Local sanghs may have slight timing differences. For many, the next day is observed as Gautam Swami’s Kevalgyan or related renewal observances. You can read more here ( jainknowledge.com)

You can read more here