I have been a web developer for about 6 years. All the work I have done, design specs and code development was for clients. I have never contributed to any open source project.

A lot of freelance / remote jobs I have came across lately require a look at your GitHub profile.

Mine is basically empty. I have my own code tracking setup, plus all the projects that I have worked on that were hosted on Github are private, so nothing will ever show on my profile page.

What can I showcase on my profile in these conditions?

I have a portfolio website where I list some of my projects, but there are only screen shots, links and descriptions of the projects, no code, for obvious reasons.