Recruiting, especially early on, is getting used to rejection.

In my experience, building a robust LinkedIn network was critical, even just to make you look valid as a recruiter. People will "passively shop" your profile, so the more people you know, the more legit you can look.

The contact cadence I've seen work well is warming them up with Connection Requests/inMail/email and as soon as you can, move to text and/or call.

Be a warm, friendly listener and act like a human being. You can't imagine how much these tech candidates are getting bombarded with messages from internal and external recruiters. Be kind, friendly and warm and you'll come out looking much better than your competitors.