It does no good to prepare when is facing a kangaroo court. The outcome is pre determined.
UPDATE: Trump Just Flipped The Script On The Impeachment Plan
A person familiar with the departures told CNN that Trump wanted the attorneys to argue there was mass election fraud and that the election was stolen from him rather than focus on the legality of convicting a president after he’s left office. Trump was not receptive to the discussions about how they should proceed in that regard.
http://populist.press/update-trump-just-flipped-the-script-on-the-impeachment-plan/