The idiom refers to the tossing (throwing) of a coin to make a choice. It means that the choice of correct answer or way forward is as random as the toss of a coin. It can also indicate that the speaker doesn't care which choice is made. It is mainly used in the sense that there is no clear difference in the choices and so one might as well toss a coin to decide.
To make a mistake
It means shut up!
flatter her to get something
he suddenly turned up (to appear, emarge)
to make something stronger ,,
The idiom buck up means to cheer up. For example one might say "she began to buck up once I showed her some photographs of her children when they were younger."
It means to concede defeat and stop trying.
It's usually just TIED UP -- it means you're busy.
It means you stood up and started giving a speech.
It means " keep calm, don't get worked up"
Getting places is no idiom that I've heard of. Going places is an idiom. It means you are successful, moving up in the world.
When you toss or flip a coin it's a 50/50 chance of it landing heads or tails up, so the phrase coin toss is used to describe a situation that can go either way.