line your pockets
US /laɪn jʊər ˈpɑkɪts/
UK /laɪn jʊər ˈpɑkɪts/

1.
to make money for yourself in a dishonest or unfair way
:
•
The corrupt official was caught trying to line his pockets with public funds.
•
Some politicians are more interested in lining their own pockets than serving the public.