To submit your application to the App Store, you require a developer certificate, a distribution certificate, a developer provisioning profile, and a distribution provisioning profile. In this section, we will bind your Mac with your iOS provisioning portal by generating certificates.
Once you log in to https://developer.apple.com, choose the iOS provisioning portal. Select the Certificates tab from the options provided in the left-hand side column as shown in the following screenshot:
If you are a first-time user, you need to first install the Worldwide Developer Relations (WWDR) intermediate certificate; this certificate binds your developer and distribution certificate to the Apple Certificate Authority. Download this and it will be installed in your keychain.
Next, let's create our developer certificate. To generate this, let's go back to our keychain application and navigate to KeyChain Access Menu | Certificate Assistant | Request a certificate from certificate...