Idioms that don't really make sense to me

So, I've decided that it's been a good life blogging here. I'll move out of this web link. I'll tell Mr. Gould though. HAHAHAHAHA.

Audience: LIAR!!!

Um...no....I'm not lying...ok fine...I am lying. Anyways, on to the real post.

Well, I've been wanting to do this for a while now. I've heard some crazy idioms. I often know what they mean, but, sometimes, I have no idea how it's supposed to mean it. So, I'll post it up, and see if you get it.

Break a leg- This is one we've all heard, but I have no idea how it represents good luck. Breaking a leg is bad luck.

Can't cut the mustard- I haven't heard this one much, an I had no idea what it meant. I searched it up, and I found out that it's someone that isn't adequate enough to compete. Well, I guess that's everyone, because no one can really cut the mustard. Who cuts mustard?

Dead ringer- Completely identical. Wow, I have no idea how "dead ringer" means completely identical.

Eighty six- No more. What? I don't know how that makes sense.

Get your walking papers-To get fired

Green room-The waiting room

Kick the bucket-Die. So...you die when you kick a bucket? Yes, we've all heard this one.

Twenty three skidoo- To be turned away. Um...what?

Well, that's mostly it. Anyone have any idea? They're all confusing to me. Especially kick the bucket. This one is the most funniest to me:

Van Gogh's ear for music- To be tone deaf. This is pretty unusual. They use Van Gogh because he only had 1 ear.

Anyways, I guess that's all. The review is coming along...pretty badly. Have I ever mentioned that I'm no good at reviewing? Bye!