For golden heros you just have to keep running - a good deck will get you there faster obviously but it doesn't matter just keep chipping away with even basic cards you can do it.
For gold farming just set it to play unranked and set concede to concede last game if won, then you can also set it to play ranked after you finish farming and play the deck you're trying to get golden.
or you can just play ranked for gold and golden at the same time, i just found the former was faster, for me when i had basic decks. i have over 90 legendaries now so it doesn't matter.
thanks hearthranger :)
