Through experience
As a software engineer and technical lead myself, I've been involved in numerous hires, and know the difficulty organizations face with finding great talent. A lot of time is spent trying to hire the right people, and more often than not a decision is made based on gut feel. As an engineer, I am not OK with this. Over the years I've learned how to identify and assess talented people, and am able to communicate that empirically. I now help businesses do the same.
With empirical data
I believe that a hiring decision should be made based on empirical data instead of intuition. After receiving a list of profiles from my clients, I contact and schedule interviews with each of the candidates. Interviews typically take 1 hour per candidate which includes a 15 minute video interview and a 45 minute exercise. Exercises consist out of technical and psychometric tests. I summarize and rank each candidate, and benchmark them against the current team.