do one's bit
• make a useful contribution to an effort or cause.
• "I was persuaded to do my bit for the environment"
Similar:
assist,
help,
lend a hand,
be of service,
give one's support,
give one's backing,
contribute,
chip in,
throw in one's lot,
participate,
take part,
join in,
get involved,
pitch in,
play ball,
tag along,
get in on the act,
muck in,
get stuck in,
