On TamaTown, there is a travel center. When your tamagotchi is an adult, you can use the ticket for your tamagotchi to travel to China, Switzerland, Hawaii, Austrailia, and Chile. Press the "B" button which is the middle button. It will take you to a screen with an airplane flying. It will then give you a code. I would suggest you have a scrap piece of paper big enough for your code to fit so you can write it down. In order to keep the code on the screen, continuously press the "C" button which appears to be the last button. When you are done writing the code, you can stop pressing the C button.
When you get the chance, enter TamaTown and go to the bottom right corner. You will see a yellow building. Enter that building and it will show you a Kuchipatchi, a Mamaetchi, and the five papers to see where you can go. Ignore that. Instead, look to the left. There is a Memetchi in a desk. Click the computer thing which says "Log In". Really, all you have to do is enter the code you got. You will get a souvenier from that certain place you traveled. Enjoy your flight
If u want to use u're ticket go to Tamatown.com and go to the travel center and go click on the broshure with the place on u're ticket and click go there.