This song is basically the best pump up song ever, besides the extreme energy of the song itself, its all about don't give up because you may not get another chance
what they mean by wake the dead is give someone another chance because if you give up on something without even trying, you will regret it forever and that's like being dead in a way
so it means just go for it, don't lose hope, don't just sit back and let life pass you by.