Pay cash for your ticket, leave your smartphone at home switched on (even script some stuff if you want to make it look like there's activity there). Boot into

Pay cash for your ticket, leave your smartphone at home switched on (even script some stuff if you want to make it look like there's activity there). Boot into a live CD, make sure you use a spoofed MAC address (does TAILS do this automatically?) and keep your face away from cameras. Should be pretty bulletproof against all but the most capable adversaries.