to tighten, fasten, or lock (something) with a screw or a device like a screw

to crush or crumple (something)

She screwed up his letter

to twist or distort (something)

She screwed up her eyes in the bright sunlight

informal to cause (somebody) to become anxious, neurotic, or emotionally disturbed

informal to cause (something) to go badly wrong

chiefly NAmer, informal to ruin (something) completely

to summon up (one's courage)

informal to bungle a task completely

For the Prime Minister to be personally involved in the Damage Control operation showed just how seriously Digby had screwed up — Ben Elton

to summon up (one's courage)