Maria Teresa Stella provides 5 design tips for improving website usability and user experience: 1. Limit fonts to two for readability. 2. Ensure all text is accessible to colorblind and low-vision readers. 3. Use colors thoughtfully as they impact emotions and perceptions. 4. Select pictures that tie to content and feel realistic. 5. Write clearly using visual hierarchy and language anyone can understand. An additional tip is to showcase your personality through visuals, animations, or unique content.