Hiring people is like sales - you have a funnel (for talent), you need to generate leads (candidates), and you need a process to nurture your leads (i.e. candidates) and move them through the funnel to a closed deal (signed offer ready to start).
The first step in all of this is to generate leads. Here are four choices for finding candidates.
First choice: Referrals from your own network. This includes student and alumni networks including clubs and networking groups. A warm introduction is always the best way - someone you trust trusts the candidate - that endorsement goes a long way and can save you a lot of time.
Second choice: Recruiters. They do cost money, but a great recruiter can save you a ton of time because they can send you qualified candidates and make your talent funnel much more productive.
Third choice: Directly post job specs on your own website and on linked in. The issue is traffic - you have to drive people there. You should absolutely post the job specs for sharing but expect low throughput from organic traffic.
Last choice: Craig’s List or similar. This generates massive amounts of junk leads and can become a huge time sink. Go this route only if you have the time and energy (or administrative help) sifting through hundreds of marginally relevant resumes to find the right person for the job.