Here's a trick to instantly boost your confidence: Walk around and eat an apple. Sounds ridiculous, but it works for me.

I noticed when work when I have a small piece of fruit in my palm my walk turns to an even strut and my chest pumps itself out without me even thinking about it. My layman's analysis is that this taps into man's deeply primitive senses of food = success. A prize openly on display; not afraid of another taking said prize.

I think apples are the best for this because of that satisfying crunch and they're not sloppy.

Give it a try! I'm curious if this works for others.