That really depends on what it is and the scenario. If you are applying to a job, including a GitHub link on the resume or 'cover letter' (email body) does the

That really depends on what it is and the scenario. If you are applying to a job, including a GitHub link on the resume or 'cover letter' (email body) does the trick. Showing up with a laptop that has your code samples could also be effective for an interview. If you ask a more specific question I may be able to give a better answer, but generally giving them access to code you've written in any form is better than no code portfolio at all.