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