Ok, the lack of topic springing to mind means what I’m gonna do is simply post on topics as they come to me.
So I’m gonna start the series on Facebook.
A long series! Forgive me if it changes later!

Day 001: Posting to a Specific Audience

One of the first things to think about is who’s going to see your post.

On the web portal each post can be managed, both before posting and then subsequently (with some caveats).
Facebook has a default (to be covered later) setting and this will be used by apps and processes that lack a direct control for privacy/visibility. However the default is applied to posts via the web portal only if you never alter the options. If you change the privacy for some reason on one post then that will be remembered next time!
The options available allow you to post to everyone, friends or even just yourself!

If you have created lists to (categories your friends) then you can publish posts specifically to them. Excellent option if the topic is likely to be irrelevant to others, possibly offensive(?).

You can choose a custom distribution. This is quite flexible. You can choose specific lists to publish to or even choose specific lists to hide the post from!

I personally have lists relating to how I know people. Where I was educated, where I have worked or my family etc.
Works for me!