Step 1: Parts List
(1) DC motor
(4) MOSFET transistors. I used the IRF540N, but any N-channel MOSFET will do.
(2) NPN bipolar transistors. I used the BC548.
(2) PNP bipolar transistors. I used the BC327.
(4) 2200 ohm resistors (red-red-red)
(4) 10K ohm resistors (brown-black-orange)
Some jumper wires and a breadboard, if desired
The resistor values are not critical. Values that are fairly close will most likely work fine.
Step 2: The Finished Circuit
Step 3: How to Use It
I'm connecting the transistor gates to positive by touching them with a jumper wire in this video, but they also are easily switched by two microcontroller I/O pins. I put a piece of red tape on the motor shaft to make it easier to see.