Yes, you can customize the appearance of the formula field button in pdfFiller. To improve visibility, use the button properties to change its color, size, and text. Clear labeling, such as 'Click to Sign', helps guide users and enhances user experience. By using contrasting colors that stand out against your document background, you can attract attention to the button, ensuring it is easily noticeable. This tip is crucial for remote professionals who frequently work with clients to ensure that every document is easily navigable.