Your web design portfolio should include a variety of your best work, showcasing different styles and types of projects. Include detailed case studies with project goals, your design process, and the results achieved.

Aim to feature 5-10 high-quality projects. It's better to have a few outstanding examples than to overwhelm potential clients with too many mediocre ones. Quality over quantity is key.

Both are valuable. Client work demonstrates your ability to meet client needs and work within constraints, while personal projects can showcase your creativity, passion, and skills in areas you might not get to explore in client work.

For each project, include a brief overview, your role, the challenges faced, the design process, and the outcomes. Use visuals like screenshots, wireframes, and prototypes to illustrate your points. If possible, include metrics that demonstrate the project's success.