[@Blackfridayrule] Well it differs from person to person, some people like writing through their character's perspective; for example:

[quote]
King Benedict sat upon his throne with the ornate table covered in documents and reports, one such paper detailed a recent sighting of foreign troops in a region that was under dispute between his kingdom - Arcoa - and the Federation of Lyria; He immediately took concern and called his military advisers to discuss the matter. Etc.
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Some prefer to do it by posting their affairs no matter who or what it affects; for example:

[quote]
The Kingdom is currently in its golden age, the King has surpassed his predecessors and the country benefits from his success. The Kingdom is at peace, there are few wars, and the agricultural reforms have bore fruit. The citizens rejoice and many want to hold a party in his name nearing his crowning anniversary. Etc.
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Although it is preferable to mix both styles, to give a "whole" picture. Like the first few paragraphs could be about the country as a whole through each region and the next paragraphs about the characters and their perspectives and so on.

And in terms of interacting with other players usually this is either done by establishing allies or competing in war and wealth. Basically politics. Politics can be driven by your nation and their description and culture or through interactions with certain things in the world.

I hope that helps. :b <- This is an emoticon BTW.