The idiom "at the helm" means to be in charge or in control of something, often referring to a leader, captain, or person who is making decisions.

The idiom "hang on" is used to express the idea of waiting or holding on until something happens. It can also be used to signal that the speaker is taking a moment to gather their thoughts or to ask someone to wait while they finish something.

The idiom "sleep tight" is used to wish someone a good night's sleep. It implies that the person will have a restful and peaceful night, without any disturbances or worries. The phrase can also be used to express confidence in someone's ability to stay safe during the night.

The idiom "hope for the best, but prepare for the worst" is used to express a situation where one wants to have a positive outcome but is also realistic and cautious about the possibility of negative outcomes.

The idiom "come to grief" means to suffer a misfortune or disaster, often involving damage or loss. It can also refer to an event that leads to the end of something, such as a relationship or business.