As an even more concrete example, all you have to do is click on the "issues" page of a project you like on github and start fixing things. Slowly work your way

As an even more concrete example, all you have to do is click on the "issues" page of a project you like on github and start fixing things. Slowly work your way up the chain from adding documentation, to fixing low priority issues, to fixing high priority issues, and then to adding new features. Looks great on a resume as well and you'll likely be able to get yourself into job interviews at the very least as you continue building your skill set.