2 stage heat 1 stage air thermostat wiring please tell me what color goes to what terminal?

The best method for a non-professional to use in home thermostat replacement is to compare the old thermostat to the new. There is however, a general color code that is normally used. Red to R, Green to G, Yellow to Y (or Y1), White to W. The question comes with W2, the wire for the 2nd stage of heat, at this stage you may be able to assume that the only one left is W2. If you are left with 2 wires, I would guess Black is common or C, and Brown would be W2. None of this is a sure thing, what really counts is what the other end of the wires are attached to.