Just stay out of their way. This is what they live for. Don't be surprised to find movie rentals and bait in the same store. Do not buy food at the movie store. There is nothing sillier than a northerner imitating a Southern accent, unless it is a Southerner imitating a Boston accent.
People walk slower here.
Don't be worried that you don't understand anyone. They don't understand you either. Eighty-five percent begin their new southern influenced dialect with this expression. One hundred percent are in denial about it. The proper pronunciation you learned in school is no longer proper.