1. Navigate to the fields page for your object.
2. Click the field label.
3. To add custom help text, click Edit.
4. On the field’s information page, you can—depending on your Edition—set field-level security, view accessibility settings, and configure validation rules.You can also do more, depending on the field’s type. For example, if the field is a picklist, you can add, delete, and reorder its values, and set dependencies. You can’t increase the field length of a standard field. If you need a longer text area, consider creating a custom field.