I won't repeat what the other comments have said because they're correct about how evolution works. Although I will say it appears that mutations might not be as random as previously thought and then, of course, you throw epigenetics into the mix and it goes to show that we really still have a lot to learn about how evolution and its mechanics work.

My response to OPs question was probably a little bit anthropomorphic in nature but I found sometimes it's easier that way when communicating scientific stuff.