I have told you a million times.
Telling someone multiple times.
You won't be sorry.
You will be glad.
Exaggerating how fast someone is running.
Running as fast as the wind.
Someone hard to get along with.
He is the sharpest tool in the shed.
Litote
As blind as a bat.
Having poor vision.
It's not rocket science.
Something is straightforward.
Someone who is sweet (Hint: an ingredient).
Sweet as sugar.
Something that could be possible.
Not entirely impossible.
Cry me a river.
Hyperbole.
Her smile was a mile wide.
She had a big smile.
It's not my first rodeo.
Sleeping for a long time.
I could sleep forever.
You don't particularly like this thing.
It's not your cup of tea.
Not a bad day's work.
Litote.
Dang, I could eat a horse.
I am very hungry.
It's not the worst thing I have eaten.
It tastes pretty good.
You're really cold, freezing.
I'm going to freeze to death.
Not being the smartest.
They're not the brightest crayon in the box.
She is older than the hills.
Hyperbole.
I'm drowning in schoolwork.
Overwhelmed by the amount of work.
He's no spring chicken.
Someone no longer young.
Someone who is strong (Hint: an animal).
As strong as an ox.
A difficult accomplishment.
It was no small accomplishment.
I love you to the moon and back.
Hyperbole.