Keep it under your hat ;)

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A bird in the hand is worth two in the bush

Butterfingers

Don't look a gift horse in the mouth

Jack-in-the-box

Cock-a-hoop

Stand and deliver

A turn up for the books

Go the whole hog

Absolute power corrupts absolutely

Back to square one

Keep it under your hat

Revenge is a dish best served cold

All that glitters is not gold

Start from scratch

Square meal

Strait-laced

A tissue of lies

A frog in your throat

Plain sailing

Fobbed off

Halcyon days

On the fiddle

A bigger bang for your buck

Old chestnut

Young turk

Damp squib

The real McCoy

Be enthralled

Get your dander up

On tenterhooks

Fine words butter no parsnips

Tawdry

Batten down the hatches

Worse for wear

Badger to death

Under the thumb

Spring forward, Fall back

The toast of the town

Gussied up

An arm and a leg

That's all she wrote