Cloe,
Here is how I hook up my motor controller to a wiper motor.
First here is the motor controller I have. It has 3 wires, red, black and blue.
On the back of the motor controller there is a label with pretty straightforward instructions.
I like to put plugs on the ends of the motor controller wires so I can plug them in or remove them if I need to change the motor controller or use it for something else. So you will need some stuff.
The motor controller, a couple pieces of small gauge red insulated wire, wire crimpers, wire strippers, and 4 end connectors and one splice connector.
Now strip the insulation off the end of the motor controller black wire and crimp on the connector. I used a female connector because I have male connectors attached to the wires from my wiper motor.
Now in the same way attach a connector to the blue wire on the motor controller.
Now comes the only tricky part. (Not really tricky. I just said that to make you think there is some really hard thing to do to make this work.) You need to attach 2 wires to the red wire on the motor controller. One to go to the wiper motor and the other to go to the positive side of the battery. To do this strip the insulation from the end of the red wire coming from the motor controller case. Also strip the insulation from one end of the short piece of red wire. Now twist the two bare wire ends together and slide them into one end of the splice connector and crimp them tightly.
Take the other short piece of red wire and strip the insulation off one end. Twist the bare end and insert it into the open end of the splice connector. Now crimp this wire tightly in the connector. Now crimp connectors on the free ends of the 2 red wires. You should now have 3 red wires crimped together.
Your completed motor controller hookup should look like this.
Now to connect the motor controller to your wiper motor all you have to do is connect the red wire from the motor controller to one wire from the wiper motor and the blue wire from the motor controller to the other lead from the wiper motor.
The remaining red wire goes to the 12v batter or other 12v power source positive side and the remaining black wire goes to the 12v power source negative side. Do not get these 2 wires mixed up or you will fry your motor controller. I speak from experience.
If your wiper motor is not turning in the direction you that want you can change the direction of rotation by simply swaping the connections from the motor controller to the wiper motor.
Just be sure to switch the connections to the motor and NOT the connections to the 12v power source. You ALWAYS want the red wire from the motor controller to connect to the positive side of the 12v power source and the black wire from the motor controller to connect to the negative side of the power source.
By the way...I always connect my lead wires on the wiper motor to the high speed connections. If you want the motor to run more slowly well, that is what the motor controller is for.
Creepy creations has a great tutorial on wiper motors. You should check this out.
I hope this helps.