(informal) it's now or never

(informal) the world's turned upside down; it's crazy; it's illogical; it's backward; it doesn't make any sense / (informal) the world's turned upside down; it's the tail wagging the dog / (informal) the world's turned upside down; that's the pot calling the kettle black

watch the birdie! say cheese!

(figuratively) to jump on the bandwagon

crime doesn't pay

(informal) and Bob's your uncle! there you have it! that's all there is to it! ta-da! shazaam!

in one's birthday suit, naked as a jaybird, in all one's glory

(figuratively) to have a strong stomach, to not be easily upset, to have nerves of steel, to have great composure

carrot and stick

you're telling me, you don't say, no kidding, tell me about it