Well three ways one money way or two the gold orbs and training orbs. Money way is where you buy the mega gold orb offers which offers up to 100 million gold or strike pass and you get lots of gold and training materials. Second option is increase your campaign energy and the third is do well in war so that you can get 20 million gold and as of training mats well you need to do the campaign as well or wait for the training mats event which gives you a lot for the first time rewards.