The candidate you are interviewing is your potential colleague in the nearest future, so treat them with respect.
Don’t feel like a god when interviewing someone. Sitting as if their life depends on you or the job shows that you are a failure.
Avoid questions not relevant to the job
When a candidate smiles, smile back too. In fact, be the first to smile to make candidates comfortable
Don’t play the devil’s advocate in interview. Be concerned the candidates potential and value propositions
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Source: Linkedin