So, first of all, go to the iTunes Store.
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Now, download a free item. It could be anything. Podcasts don't require an account, so no use in trying. Download an app. It's fine, you don't need to own an iPhone or iPod touch. Just download an app.
Next, iTunes will ask you to create an account or sign in. Choose to create an account. That's what you want. So go ahead.
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Now, accept the agreement as you would and start entering your details.
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Now, on the next page, it asks for your payment method. This is used only for purchasing things. An Apple account is completely free. Because you are downloading a free app, see carefully. You have a special option:
[caption id="attachment_67" align="aligncenter" width="450" caption="See, there's the 'None' radio button. Select it!"]
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You're done. Complete the registration and activate it from the email. You now have an iTunes account. Congratulations! Now, whenever you try to download a paid item, Apple will greet you with this:
[caption id="attachment_68" align="aligncenter" width="450" caption="Enter your password and click billing info to supply your payment details which you had skipped"]
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