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To leverage existing work and reuse the fields on other group types, a Contact Info paragraph bundle was created ahead of time.

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D8 Group - Create Group Type - Add Fields - Click Manage Fields

1. Manage Service Group Fields

From the Group Types tab, locate the Service group type and click its Manage Fields button.

D8 Group - Create Group Type - Add Fields - Click Add Field Button

2. Add Group Contact Info Field

Click the Add Field button.

D8 Group - Create Group Type - Add Fields - Define Group Contact Info Field

3. Define Group Contact Info Field

Add a New Field select field = Paragraph.

Label text field = Contact Info.

Click the Edit Machine Name link.

Machine-Readable Name text field = add the word group and an underscore to the front of the name - ex: group_contact_info.

Creating a consistent naming convention for your fields will pay off greatly in the long run.

D8 Group - Create Group Type - Add Fields - Save Group Contact Info Field Settings

4. Set Number of Values

You'll be redirected to the Contact Info screen.

Type of Item to Reference select field = leave set to Paragraph.

Allowed Number of Values select field = select Limited, 1.

Click the Save Field Settings button.

D8 Group - Create Group Type - Add Fields - Select Paragraph Bundle

5. Select Paragraph Bundle

You'll be redirected into the full settings screen for the Contact Info field.

Label text field = leave at Contact Info.

Help Text text field = add some help text if preferred.

Reference Method select field = leave at Default.

Which Paragraph Types Should be Allowed option buttons = select Include the Selected Below.

Paragraph Types check boxes = choose Contact Information (leave the others unchecked).

Click the Save Settings button.

D8 Group - Create Group Type - Add Fields - Contact Info Field Saved

6. Contact Info Field Added

You'll be redirected to the Manage Fields list for the Service group type.

You'll see the new Contact Info field in the list.

D8 Group - Create Group Type - Add Fields - Click Add Field Button

7. Add Group Description Field

Now let's add a Description field for the group.

Click the Add Field button.

D8 Group - Create Group Type - Add Fields - Add Description Field

8. Define Description Field

You'll be redirected to the Add Field screen.

Add a New Field select field = Text (formatted, long).

Label text field = Description.

Click the Edit Machine Name link.

Machine-Readable Name text field = add the word group and an underscore to the front of the name - ex: group_description.

Click the Save and Continue button.

D8 Group - Create Group Type - Add Fields - Save Description Field Settings

9. Limit Number of Fields

You'll be redirected to the Description field settings tab.

Allowed Number of Values combo field = leave set to Limited, 1.

Click the Save Field Settings button.

D8 Group - Create Group Type - Add Fields - Finish Description Settings

10. Finish Description Field Settings

You'll be redirected to the Edit tab.

Label text field = leave set to Description.

Help Text text field = add help text, if preferred.

Leave all other fields as is.

Click the Save Settings button.

D8 Group - Create Group Type - Add Fields - Description Field Added to List

11. Completed Group Description Field

You'll be redirected to the Manage Fields screen for the Service group type.

The new Description field will be in the list.