Screw up your courage - Idioms by The Free Dictionary
screw up your courage
screw up (one's) courage
To emotionally prepare oneself to do a frightening or overwhelming task. I'm really nervous about asking Sarah out on a date, but I just need to screw up my courage and go through with it.
screw up your courage summon up all your courage; force yourself to be brave.
References in periodicals archive
What's up?" b) You screw up your courage
, propel yourself toward the food court, and yell, "Hi, Jack!" a little, um, loudly.