You need Manage company settings permission.
1
Go to creation dialogs
Go to Settings → Data customizations → Creation dialogs.
2
Choose the record type
Select Clients, Prospects, Contacts, or Businesses.
3
Choose and arrange fields
Select built-in fields and custom fields. Drag fields in the preview into order or rows, and drag their edges to resize them. First and last name, or the business name, must stay in the layout. When creating a client, prospect, or contact, enter a first name or email; last name is optional. Businesses require a name.
4
Save the layout
Click Save changes. Restore defaults resets the selected record type’s layout before saving.