I think you should take them right before you leave the house(or at the airport like the guy above me said)...i think you should also split the weed up into more crackers i usually put about .3 -.5 in a cracker with mids and the high last around 5 hrs after eating 3

Just a suggestion so you won't have to use all your weed if u dont want to

Edit: You might wanna take eyedrops with you incase your not trying to get caught. A lot of people still get red eyes from edibles