Ask HN: How to make a portfolio for a hardware engineer?

I am mentoring a university sophomore who is studying engineering. I suggested that he make a portfolio of his projects to (1) sell himself for internships and jobs, (2) motivate himself to do better projects, and (3) improve his communication and presentation skills.

If anybody has made such portfolios, do you have advice on how to proceed? Pointers on how to craft a good portfolio is appreciated, as are pointers on where to host one. Thanks.