Don’t, it’s not worth it.
NASA constantly deceiving != the earth being flat
Flat Earth, in my estimation, is basically a “political wedge issue” of the conspiracy community. It has no real bearing on the lives of 99% of people, but so many just have to pick a side and fight over it.
Seriously. Nothing about your day to day life changes one way or the other, there’s no need to froth at the mouth over the topic, flattard or nasahole alike. Who cares?
Now that’s not to say, don’t spread facts and logical arguments about specific things, like the Van Allen radiation belts, or the {fake} moon landings, or whatever. But just dont tie your identity to the false totem of either “Flat Earth” or “Globe Earth”, it really has almost no bearing on your life, other than that which you give it, like any totem.
What established their lies to work? Consent to believe the offer of others. What are you doing when using flat earth truth against globe earth lies? You're suggesting them to consent to believe yet another offer aka switching sides within the same conflict of reason (believe in truth vs false).
Why do you not address the cause (belief) within the many; but only cover up the symptoms of the few (lies) with your proclamations (truths)?
Reason perpetuates conflict, which represents endless division, and what causes reason? Consent to belief offered.