Don't strike out before you start.
Job search is a state of mind, not an activity. What does that mean? It means that when you are looking for a job, in the back of your mind should always be, "What if a hiring manager could see me right now?" This may seem a bit extreme, but there are countless stories of huge mistakes people have made, killing their chances right out the gate. There was a guy that I called to schedule an interview. He looked impressive and I wanted to move quickly so he wouldn't be hired els