Most universities request a portfolio in a pdf format with size specifications clearly stated. It is helpful to study the architectural styles that the institution prefers. Consider deciding on a theme that expresses your style best. Skills in graphic design are essential to building an impressive portfolio. Learn tools like Adobe Illustrator, Adobe Photoshop, Adobe Indesign, Behance, etc. Include any information, photograph, or work that may add to your personality. Be careful to include the right amount of samples to avoid cluttering.