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Navigate to Setup » Build » Customize » Contacts » Fields or to set-up Lead navigate to Setup » Build » Customize » Leads » Fields. Within the fields page navigate to the Contact or Lead Custom Fields & Relationships section
Figure 16: Customising Contact Fields
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If a multi-select picklist or picklist field is required, make the values for the picklist the same as the roles that are required. For example, if a requirement was to allow users to add contacts to the ‘Example Role 1’ role – we would add ‘Example Role 1’ to the list of picklist values.
Figure 17: Multi-Role using multi-select picklist
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If checkboxes are required, add a checkbox for each role. It is important to ensure the checkbox field label is the same as the required role name.
Figure 18: Multi-Role using checkboxes
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