Help a Luddite Please?

So the Supernatural premiere next Wednesday is going to be preempted in Chicago for a baseball game because the Cubs made it to the playoffs...

(Cue agonized wailing...)

Can anyone talk me step by step how to get it live on my laptop? Maybe a way to test it on another show before next Wednesday? I tried once before to do that but got very confused by the multitude of sites and the hoops I was supposed to jump through...