You can do this by going to http://support.xbox.com/billing-and-subscriptions/account-management/xbox-live-account-management and following the account closure process.
Para sa Xbox, maari mo itong gawin sa pagbisita sa http://support.xbox.com/billing-and-subscriptions/account-management/xbox-live-account-management at pagsunod sa proseso ng pagsara ng account.