As a manager who hires developers:
- A candidate's publicly readable source code makes a big difference.
- Most candidates have no public readable source code, but the ones that do, typically have 3-5 projects, with 1 or 2 showing activity within the last week.
- Some candidates game the 'recent activity', by making commits in the week before an interview. I notice, but I'm still impressed with the effort.
- The number one thing a rookie coding candidate can do in an interview is convince me that they know how and when to ask questions. Rookies who don't stop to ask questions can waste a lot of time and do a lot of damage.
- Do use a recruiter, if you're able. I have a few I trust, and if you can impress yours, they can get you an interview with me when I'm otherwise too busy. You'll also get more money, because they get paid based on what you get paid.