How do you match speakers to match a 4 ohm amp?

There is no need to match a 4 ohm speaker to a 4 ohm amp, because there is no 4 ohm amplifier on the market. The amplifier will have an output impedance of around 0.04 ohms. In hi-fi we have always impedance bridging. Zout << Zin. The damping factor DF = Zin / Zout tells you what Zout is. Zout = Zin/DF. If the damping factor DF = 100 and the loudspeaker impedance is Zin = 8 ohms, the output impedance of the amplifier is Zout = 4 / 100 = 0.04 ohms. You see, there is really no "4 ohm amplifier" with a 4 ohm output. Scroll down to related links and look at "Voltage Bridging or impedance bridging - Zout < Zin".