The answer is don't. If you all are smart, you'll start a "zero tip" movement and put an end to this nonsense before you end up like we are in the US. Some jackasses will attempt to frame the argument as about the workers. It's not. Business will abuse basic human kindness to turn this into a way to offer less pay and benefits. If employees want more pay (or anything for that matter), they should be organizing to claim it from their employer, not trying to get their fellow working people to make salary decisions. Please believe that tipping has no pleasant end for anyone but the wealthy.