Take it to your Dojo but leave it there if you use it there. If you use it at home leave it there or transport it in a car. We can not carry a Sword sins the Samurai days my friend. Samurai tryed to fight this but, they dyed out and the rule stands that you cant carry a sword with you.
If you ever get stopped i think all you need to do is tell them you go to martial arts so be sure to have a card handy If your not sure ask your instructor. ^_^