horn button relay

I have a 66 mustang and the horn button does not work. I tapped into wires going to the old horn button on the steering wheel with a momentary toggle switch. This worked for a while but I think it’s drawing too much amperage, One yellow wire that I taped into is constant hot with power coming from the headlight switch going to the old horn button on the steering wheel and the other blue wire(Not Hot) goes from the horns into the steering column to the old horn button.   I just used two quick taps under the dash right to the new momentary toggle switch. Does anyone know how to wire this momentary switch using a relay? A diagram would be great. Thanks, Sobz Sobz

John, thank a lot for taking time out to research this project. Regards, Bob SobersSobz