I take an athletic approach to the tee box, and although you may not be the athlete you once were, you can tap into your innate skills anytime by staying loose and relaxed. Golfers tend to make hurried, uncoordinated swings when they're tense. That's why when I step on the tee, I take a deep breath. As I inhale in and out, I can almost feel the tension drip out of my body.
When I'm free like this, my swing speed goes off the charts. If the breathing trick doesn't work for you, try making your body as tense as possible, and then let every muscle go slack all at once. By going from taut to loose you'll start to understand what "tension-free" really means.