A word to the wise
A piece of advice given to someone who is already knowledgeable.

Take it with a grain of salt
Don't take advice too seriously; consider it with skepticism.

Get a second opinion
Seek advice from another person, especially a professional.

The proof of the pudding is in the eating
The real value of something can be judged only from practical experience.

Better safe than sorry
It is wiser to be cautious than to take risks.

Take the bull by the horns
Face a difficult situation directly and with courage.

You can't have your cake and eat it too
You cannot have both of two desirable things; you have to make a choice.

Look before you leap
Think carefully before taking action.

Don't put all your eggs in one basket
Don't risk everything on a single venture; diversify your options.

Actions speak louder than words
What people do is more important than what they say.

A penny for your thoughts
Asking someone what they are thinking or for their opinion.

Give someone a piece of your mind
To tell someone what you really think about something, often in a blunt way.

Haste makes waste
Acting too quickly can lead to mistakes and wasted effort.

A leopard can't change its spots
People cannot change their innate nature.

Bite the bullet
To endure a painful or unpleasant situation that is unavoidable.

On the fence
Undecided about something, unable to choose a side.

When in Rome, do as the Romans do
Adapt to the customs of the places you visit.

Steer clear of
Avoid something or someone.

Don't count your chickens before they hatch
Don't assume success before it actually happens.

Let the chips fall where they may
Accept the consequences of your actions, whatever they may be.