When my two kids were a little younger, we tried a
YouTube moment and announced the very day we were leaving, that we were going to WDW. To build to that moment, we created small wrapped gifts for both of them. Included in the gifts were little toys, books, and t-shirts. They opened the gifts on video.
The t-shirts were plain white Ts and I used a computer generated design on the Avery iron on. How I worded it was this, "I'm on my way to Disney World for a week!" Or something like that.
That way when my daughter read the t-shirt, she instantly understood. Her brother wasn't reading at the time and she explained to him on the video we shot.
Later when they both wore their t-shirts to the airport, the pilot of the SW aircraft strolled by and saw them too. He gave them high fives before boarding the plane. The flight attendant saw them too and gave them extra stuff during the flight. Everyone who saw the t-shirts knew where these kids were headed.
It made it way more exciting for them both to have other people comment on their trip.
In review, the video was a big bust. Neither reacted like we thought they would. Even with the t-shirts in hand, they still couldn't grasp that we were leaving TODAY... like RIGHT NOW. We have to go to the airport now. My son simply walked away to play with his new Disney related toys.