In Xcode open the preferences

1. In preferences click on Accounts

2. Select your developer Account

3. Click on the circle icon with the 3 dots

4. select Export Apple ID and Code Signing Assets...

In the new dialog window

1. enter the desired filename of the export file

2. Enter a password  (this password is later needed to import the file in Xcode on the new computer)

3. re-enter the password

4. Press Save

You will then asked several times for a password to access the private keys in your key chain.

After successful export you'll see a pop-up window showing the total number of accounts, code signing identities and provisioning profiles* that were exported.

* please see the note about Provisioning Profiles in the chapter about Importing the developer profile into Xcode on a new Mac.

On the new computer either double click the export file and continue with step 4 or open Xcode and go to Preferences

1. In Preferences click on Accounts

2. Click on the circle icon with the 3 dots

3. select Import Apple ID and Code Signing Assets...

4. in the next dialog select the file which contains the exported developer profile

5. enter the password you've entered when exporting

After successful import you'll see a pop-up window showing the total number of accounts, code signing identities and provisioning profiles that were imported.

1. Press okay to close the pop-up window.

Note: It seem that although the developer profile contained also provisioning profiles (see 1.3) those provisioning profiles were not imported back.

2. S to load those provisioning profiles from your developer account just click on Download Manual Profiles.

To check if the provisioning profiles were downloaded go to folder  ~/Library/MobileDevice/Provisioning Profiles