Couple of ways- stop accepting overtime, stop flying as an FO if you are a Captain, dump your union altogether (go unionless) and let anarchy reign, don't engage in bargaining that lowers quality of life in exchange for more airplanes or flow agreements. If its not a great place to work, smarter people won't work there and nature will just take its course. Let the company decide if they want more airplanes or flow to attract new hires, it has nothing to do with you.