First open iTunes, scroll down and click the U.S. icon on the bottom right corner.
On the next page, select Japan from the list of countries. Next, click the “Sign In” button in the upper right corner of iTunes. Next, you see a popup with the option to create an Apple id–click the button.
The next page welcomes you to the iTunes store, click the continue button.
The next page requires you to check the agreement box and click the “Agree” button.
On the next page you’ll enter your email, create a password and complete other information then click “Continue.”
Next, you’ll complete your billing information and address. If you are redeeming a Japanese iTunes card enter the code and leave the credit card info blank. Enter your Japanese address too–JBOX will tell you how to complete that. Click the “Create Apple ID” button and you’re done. By the way, a U.S. credit card will not work.
Some customers have reported that iTMS won’t let you proceed without entering a credit card. In order to bypass this, hit the “Home” button and begin the Redeem process again, and you’ll see the “None” button the second time through. — JBOX