Whats the best way to get onto an airplane?

Me and my girlfriend are going from chicago to orlando, but my girlfriend is a immagrant. whats the best way for her to get onto the airplane. i called TSA and they said her consulad id is fine. ive heard just do not show id and ive heard lots of different things. whats the best way for her to get onto an aiplane without trouble? Shes from mexico by the way