How to Change Your Apple ID Password
If you can't remember your Apple ID Password, or want to change it, use the iForgot Password Retrieval process. Follow these steps to change your Apple ID Password:
1) Go to iForgot.apple.com.
2) On the Password Retrieval page, enter your Apple ID Name and click the Continue button.
3) Choose Option 1 to request an email from Apple, or Option 2 to answer the security question you set up when you first created your Apple ID.
4) By following the emailed link or answering the security question, you'll be presented the option to reset your Apple ID password.
See How to Change Your Apple ID Name if you'd like more information.