Step 1: Opening.
I hope this letter finds you in the best of health and spirits. With Diwali approaching, I am eagerly waiting to celebrate it in my native place.
Step 2: Invitation.
I would be delighted if you could come to my native place during the Diwali holidays. The festival here is celebrated with great joy, decorated houses, bright lamps, sweets, and fireworks. It will be a memorable experience for both of us.
Step 3: Closing.
Please do come and spend this Diwali with me. Convey my regards to your parents. Looking forward to your positive reply.
Yours lovingly,
ABC.