Assume that whatever social interactions I have are going to come back to me in twenty years, so try not to make my future self too embarrassed; be as polite and respectful as feasible.
This is true but tricky; Many of the behaviours that I have previously thought of as polite or respectful I've later learnt come off as detached, dismissive, or abrupt. And asking people about what politeness or respect means to them is surprisingly uninformative.
So I personally find this useful only once it's simplified to essentially Right Intent -- ie. act out of intent to improve the overall situation, not malice, spite, fear, or jealousy. Anything more complex I find too confusing to accurately apply in realtime.
I'm not as smart as I like to think I am. Knowing that, I've gotten into a habit of trying to work out as many general principles as I can ahead of time, so that when I actually need to think of something, I've already done as much of the work as I can.
What are your most useful cached thoughts?
A few of the rules-of-thumb I've already pre-cached include:
That should be a reasonable but not overwhelming sample of the sorts of ideas I mean, and am hoping to evoke more of with this post.