The principle is to look at the last word of the previous post's sentence and build a coherent new sentence with the single letters of that word, while these letters (in order) represent the starting letters of your new sentence. You could also just describe it as a type of abbreviation, though the more valid term would be acronym.
The sentences needn't make sense at all costs, but should at least be grammatically flawless. I give you three examples how it might unfold. It would be neat if everyone keeps the habit to display the last word in bold to highlight the relevance as well as enhance the clarity.
My mother is 42 years old.
Officers lack devotion.
Demons evoke various outward tension in our neighbourhood.
(oh well, that's a long word for the start, if you seek less challenge pick nation instead )