I’ve developed a four-step strategy for making Twitter morally useful.
Step One: Compose your tweet
It will be best to do this with as little reflection and revision as possible. Simply compose your tweet as you are led by external circumstances and internal dispositions. N.B. Quote tweets can be especially instructive for the purposes of this exercise.
Step Two: Hold your tweet up as a mirror of your soul
This, of course, is the difficult part, but, after a moment’s effort, it should not prove all that challenging. But it will require a measure of honesty to oneself and careful attention to what one is actually thinking and feeling. Perhaps you begin with a simple question to yourself: Why? Why am I tweeting this? Not ostensibly, but in reality. Additionally you might the following: What do I hope this tweet will accomplish? What is it likely to accomplish? Who is the real, again not ostensible, audience? Etc. You get the idea. Finally, reflect on what the answers to questions like this reveal about you.
Step Three: Delete the drafted tweet
Its work is done. Delete the draft. Don’t think very long about this. Just do it. Everyone, including you, will be better for it.
Step Four: Repent, do your penance, resolve to be a better human being, etc.
Seek the counsel of your moral/religious/spiritual tradition for how best to proceed along the path of moral growth.
Of course, this post is written in a somewhat facetious spirit, but only somewhat. I should add, too, that I don’t certainly don’t like what I see when I hold Twitter up as a mirror of my soul. And, yes, you could perform this exercise with other platforms; Twitter rather focuses the matter for me.
L.M. Sacasas 
To think I enjoy the benefit of such bon mots regularly since L.M. became a co-worker…and I have the added benefit of their moral usefulness!
Well, “added benefit” is questionable!
In addition to the *process* of posting, which you’ve cleverly highlighted here, I think the *time* of posting also matters. I have the tendency to tweet at night when I’m exhausted from teaching and just want to unload what’s been simmering for six hours. Hasn’t turned out well (based on the kind of person I want to be). Over the past few months, I’ve composed drafts in the evening but left them to be posted in the morning. When I reread them in the morning I realize how silly or erroneous or despicable they are. Obvious, but easily forgotten, I’ve come to see I’m a much different tweeter at 10 am than I am at 10 pm.
Good point.