(informal) to imagine things, to have another think coming, to be deluded

(vulgar) to get lost, to go to hell, to go fuck oneself

(figuratively, informal) to get one's hands dirty

(figuratively) to sit back and do nothing

Alternative form of retrousser ses manches

(informal) to do a bunk, to take French leave, to skip town

(transitive with à) (informal, figuratively) to try one's hand, to get one's hand in, to get accustomed, to train oneself, to practise

(informal) to tie oneself in knots, to worry oneself sick

(informal) (transitive with de) to make fun of, to laugh at, to take the piss out of

(informal, figuratively) to get a tan, to bask in the sun