Well, I would take with me a notepad with a written story by me containing the 12 words of the seed distributed along the whole text, very well disguised in a way nobody could suspect anything. You just need to be creative to create a coherent tale, what shouldn't be so hard, since seeds' words are really common ones, being possible to add them to any fictions easily.
And I doubt someone would steal a cheap notepad from your luggage or seize it, because there isn't any reasonable cause to justify that at first point.
This suggestion has been given by few people here and guess what the staff at the airports are reading these suggestions too.

Next time if you see them looking at your notebook and taking interest in the story written on that notebook, be alert, they are searching for your seed
Hahaha! If they get too interested on the story, then the crypto enthusiast might think about publishing a book and nobody will be able to identify which are the seed's words yet, since they will be among so many others.

Moreover, it must be a good marketing strategy to advertise a book: hey, my bitcoin wallet's seed is on this book, find it if you can and the btcs held there will be yours (but you need to buy the book first)!

Going abroad, why you should buy a cheap notepad? Is it forbidden to travel with a laptop or iPhone?
I was traveling to Germany, I had an iPhone with me and I took my laptop with me, no problem.
The thing in Notepad is a very trivial thing, it can be lost at any time, so if you want to write a story, you can save it on your iPhone or laptop without writing it in Notepad, It is much safer.