Do your children get screen time? Switch them to Chinese media or games. Switch all your devices to the Chinese language. (Of course, this might prevent YOU from using your devices but that just forces you to spend more time with your family.)
Can you speak Chinese but feel it’s not good enough or too much effort to think in your non-dominant language? Start switching to Chinese when you speak to your children, perhaps just 10 minutes a day and then gradually ramp up the time.
Do you read or tell stories to your children before bed? If possible, start reading Chinese books or putting on Chinese story CDs.
The idea here is to think of all the things you’re currently doing with your children and try to turn them into Chinese versions. It will be really difficult at first (or even longer). But it will be worth it in the long run.