For example, my friends are talking about something interesting. They seem to never stop talking. I want to take a part in the conversation but I can't wait for my turn to talk. In this case, I'll say that I can't get a word in edgeways.
Here is another example. I fell in love with a handsome guy. Today I'm going to phone to my friend and I want to tell her about this guy=) I think I'll say something like that: "Guess what? Last night I met a guy. He was so handsome! I definitely fell in love with him. Oh!I have butterflies in my stomach!"
And one more. This is my favourite idiom. I wouldn't say that it's an idiom. I'd better call it a phrasal verb. However, my coursebook calls it so.
Imagine that I want to have breakfast but there aren't cornflakes. So I'll tell my brother: We run out of cornflakes. Please, buy some ones when you back home from the work."