New Furnace won't turn on after trying to install thermostat
Jump red to green and see if the indoor blower runs, if so you have 24 volt power and the transformer and 3 amp fuse on your circuit board are fine,if not check the 3 amp automotive type fuse found on your circuit board.
If you have no fuse the transfomer may be bad from touching red to Common a direct short which fries the transformer. Is there a diagnostic light on your furnaces circuit board?  if so is it flashing or staying lit? is there correct high voltage as well as the 24 volts?
Breaker tripped?