Sometimes, or most times, our brain can be our own worst enemy. Its default setting is self-preservation and that mode knows squat about the big picture.
To remedy this, Mel Robbins invented the 5-second rule. It's quite simple really. When you get a thought worth acting upon, like "I should cold call that big shot CEO", or "I should go over and ask that girl out", you should act within 5 seconds. That way you'll work faster than your brain can kick in its all too familiar "voice of reason".
Here it in her own words in her now famous Tedx talk.