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.