Job interviews are nerve-wracking even if you know you're qualified and capable. If you're highly nervous, the best thing to do is to say as much to your interviewer.
Interview picture from Shutterstock
Recruiter Ann Mehl suggests in a video interview with OneWire that this is a case where honesty is usually the best policy:
I often say to folks, when you get to the meeting, if you feel nervous and you're sweating and you're feeling like you're panting, admit it. Say it. Drop it into the room. Just say, "My nerves are getting the best of me right now and I just want to admit that." Because the other person is human and I think they'll relate to you more if you share it than if you're all strung out."