// For complete examples and data files, please go to https://github.com/aspose-words/Aspose.Words-for-.NET.git.
Document doc = new Document(MyDir + "Form fields.docx");

FormFieldCollection documentFormFields = doc.Range.FormFields;

FormField formField1 = documentFormFields[3];
FormField formField2 = documentFormFields["Text2"];

formField1.Font.Size = 20;
formField2.Font.Color = Color.Red;