Um, do exactly what they have been doing? A big helping of "blame the pilots" with a side of "third world airline" (*) and a dash of American exceptionalism.
One of the problems is that now people realize what an ancient aircraft the 737 is. Safety procedures that can tear the skin off of the pilot's hand or break his knee do not exactly shout out "modern technology." The plus side of such old technology is that it is tested and proven, but then two crash due to software bugs.
I think Boeing has bigger problems with perception than the 737 MAX at this point, but as far of the MAX goes they have really messed up since their primary customers are overseas. The US is probably easier to deal with because of the exceptionalism bubble; you can see it in the posts here. People still say that US pilots don't make errors, despite two hull losses by US airlines since the Lion Air crashed.
(*) Any airline based in a country that USians can't locate on a map, which is pretty much anywhere.