Not your cup of tea
You do not prefer it; not to your taste; not your favorite
Miss the boat
To lose a chance; arrive late or miss out on something
Mind your P's and Q's
To be mindful of what you say and what you do; to mind your manners
Nitty Gritty
The details about something; the core or root of something; the most important part
Needle in a haystack
Something that is hard or impossible to find; hopeless in a search
Old wives' tale
A superstition
No spring chicken
Not young anymore
Off the wall
Shocking, very unusual
Off your rocker
Crazy, silly, foolish, not thinking correctly
On cloud nine
Blissfully happy; joyous