I've been reading people previous posts on kill switches, but I had one question. If I use one of the ignition wires and wire it up to a button, do i need to have the button pressed all the time or is it ok to only press it when i start the car and then forget about it? If so what's the best way to do this?

depends on which wire you choose to cut, if u take the wire that only has power on it during the cycle of ur car in start then yes a push button will be fine, other wise just use a toggle

Well mine is a wire connected to a screw & I keep my finger on only as the starter motor cranks or only get REDS.