1. Run way slower than you think you should.  Don’t fall into the trap of thinking you’re going to run as fast as you did in high school (if you even ran in high school – that’s certainly not a prerequisite).  The point is, you’re old and out of shape now, and you just need to work with what you have.  When you’re first starting out, you should probably feel like you could walk as fast as you are running.  It should feel like it’s too slow, and you’ll never get a workout this way.  Trust me, you will.  See how that pace goes for an extended period of time and then gauge whether or not you think it’s too slow, for realsie.  Too many runners start out fast and quickly crash and burn, end up feeling like ass, and then never want to run again.  Start by being a…