Have bigger fish to fry
Eat humble pie
Sell (go) like hot cakes
Take something with a pinch of salt
The icing on the cake
Piece of cake
Put all your eggs in one basket
Sweeten the pill
Have a lot on your plate
Get (have) egg on your face
Spill the beans
To look stupid because of something that you have done
To have something more important to do
To be bought quickly and in large numbers
Reveal a secret
Something very easy
to not completely believe something that you are told since it may be false
Attractive but inessential addition or enhancement.
to have a large amount of important work to deal with
To depend for your success on a single person or plan of action
To admit that you were wrong
To make something bad seem less unpleasant