A
Butterflies in my stomach
I'm nervous
It's raining cats and dogs
It's raining really hard
You're a couch potato
You're lazy
I'm all ears
I'm listening, you have my full attention
Break a leg
Good luck
You're barking up the wrong tree
You're looking in the wrong place or asking the wrong person
At the drop of a hat
Do something instantly
Beat around the bush
Talk around something, never get to the main point
Don't bite off more than you can chew
Don't take on more than you can handle
Bite the bullet
Endure a bad situation or get it over with. Has to be done
They're a dime a dozen
They are common, inexpensive, can be bought anywhere
Don't add insult to injury
Don't make it worse than it is
By the seat of your pants
To do something luckily by instinct or without preparation
By the skin of your teeth
You barely missed it, narrow escape
Call it day
The end of something. We are all done
I'm all thumbs
I'm clumsy/awkward
Quit busting my chops
Stop getting at me, scolding me, harassing me
Clam up
Have a cow
Overreact, make it a big deal
Get bent out of shape
To get offended, worked up, mad, annoyed
Fit as a fiddle
Feeling good, nothing wrong, in good shape
Let the cat out of the bag
Reveal a secret
Spill the beans
Tell someone's secret
Off the hook
Right as rain
Something is perfect