The great Hindu festival of Diwali will be celebrated this year on 12th November.
On this occasion I appeal on behalf of Ibaadatkhana, a global organisation promoting inter faith harmony, of which I am the patron, to all non Hindus worldwide to celebrate Diwali on that date. Some details of Ibaadatkhana are given below
https://indicanews.com/ibaadatkhana-function-and-unity-dinner/
https://indicanews.com/the-historical-importance-of-the-ibaadatkhana-movement/
I may mention that for the last 25-30 years I have been keeping one day roza during the holy month of Ramzan or Ramadan ( usually on the last Friday )
https://indicanews.com/justice-katju-my-experience-of-keeping-roza/
I am an atheist, but I respect all religions, and strongly support freedom of religion and inter faith religious amity. I keep one day roza during Ramzan as a symbol of respect for my Muslim brothers and sisters, and each year I appeal to non Muslims worldwide to do the same.
It may be mentioned that at one time Hindus would participate in Eid and Muharram, and Muslims would celebrate Holi and Diwali. Even the Mughal Emperors like Akbar, Jehangir, Shah Jahan, and the later Mughals upto Bahadur Shah Zafar, as well as the Nawabs of many kingdoms in India like Avadh and Murshidabad would celebrate Holi and Diwali.
http://scroll.in/article/800900/in-mughal-india-holi-was-celebrated-with-the-same-pomp-as-eid
Diwali was also known as Jashn-e-Chiraghaan, and celebrated by Muslim rulers with great enthusiasm
https://thewire.in/history/how-the-mughals-celebrated-diwali
https://www.deccanherald.com/features/a-platter-of-unity-1044992.html
Later, after the Mutiny of 1857 the British rulers started the nefarious practice of divide and rule, and sowed the venom of communal hatred, because of which this practice largely stopped.
https://www.punjabtodaytv.com/english/communal/
It is time now to revive and renew the affable and amiable custom of celebrating festivals of all religions together. I am confident non Hindus everywhere will pay heed to this appeal on behalf of Ibaadatkhana, and celebrate Diwali on 12th November this year..
As to how to celebrate Diwali is upto you. One way you could do it is by lighting and placing a ‘diya” or earthen lamp in front of your houses ( or if that is not available, some other kind of lighting ), and greeting your Hindu friends with some sweets