Usage patterns
〈人〉の手伝いをするto help someone (with a task)
手伝いを頼むto ask for help
I asked a friend for help with the move.
手伝いに行くto go to help (out)
I went to help prepare for the festival.
〈人〉を手伝いに雇うto hire someone as a helper
The shop only hires helpers during busy periods.