whatever helps you sleep at night

bank night

An event where patrons are enticed to buy entry tickets into some venue, for example a movie theater, with the anticipation that they will be entered into a drawing to win an amount of money if their ticket is drawn and they are on-site at the time of the winning.

beauty sleep

Originally, sleep taken before midnight, on the belief that early sleep hours conduce to beauty and health; now (chiefly humorous), sleep at any time needed by one to stay beautiful; (countable) an instance of such sleep.

big sleep

Death.

call it a night

To go to bed to sleep.

call it an early night

To go to bed or cease one's activities earlier in the evening than usual.

creature of the night

A prostitute.

cry oneself to sleep

To cry until or to fall asleep.

day or night

At any time; 24/7