Nonviolent noncompliance, work stoppages, boycotts, sanctions, divestment, and further peaceful and effective measures until there are uniformly people in critical positions of power not beholden to the billionaire robber barons. Make it a criminal offense to be a paid lobbyist, abolish PACs and Citizens United, and every elected official profiteering. Keep going until wealth is firmly subordinate to civil authority. There is no perfect or magical plan that can be conveyed by a few sentences, so if you're out for a gotcha answer, you're not going to find a risk-free, batteries-included, cookie cutter blueprint anywhere from anyone.