How do I pull my whammy bar for dimebag harmonics?

You have to have a double locking tremolo (generally referred to as a whammy bar) to do that. Your guitar has a syncronized tremolo. It doesn't pull backwards. It only goes forward to loosen the strings. I'm sorry that you bought this guitar if you want to play "dimebag" style riffs. Because it physically can't do it. The bridge your looking for is a Floyd Rose. It has fine tuners on the bridge and a locking nut. so it will not go out of tune when you use it.