Potentiometer question

Hi, I am using 12V truck wiper motors, and arduino uno and monster moto shield to control my simulator. It is 2DOF. I do not know about potentiometers and have never used them before. Thus, I am wondering how to connect them to the motors and how to use them correctly. Thanks for your advice in advance.

There is a few ways to connect them to the motors , I use big worm gears that have a hollow centre output shaft this allows me to build my own lever then drill out one end to mount the pot into like pictured below.
A few people use shaft couplers , you can buy them at most hobby rc shops, and some even come with different size holes on them, so one side matches the bolt out of the motor and the other matches the pot.

Ok a quick crude little lesson on what the pot does, its a variable resistor as you turn it from its min to its max the value (output voltage) increases , turn them the other direction it decreases.
Like a volume knob on a tv or stero , Now what we use them for is to track(feedback) the exact position the lever is in so that the Jrk,Ard knows what position it is in and then can decide on which direction it needs to turn in, in order to meet the next position command SimTools sends it.

On cheap pots there is normally a tag to stop them from rotating once mounted , the pin closest to this is normally the Ground pin , and the next one along is the wiper pin (Output Pin) , last pin is normally the Power in Pin (Input Pin). For example if the Input pin is 5v's and the pot is turned half way the Output Pin will have about 2.5v's present on it.
Most pots have a datasheet which will tell you what each pin is.
Google can provide a wealth of information.

There is another connection method that use a strip of plastic , fixed at one end to the pot and the other has a long slot and slips over the end of the lever ( not the centre) and as the lever rises and fall it turns the pot but if the lever does a full 360 degrees (as in motor went mad) it doesn't end up breaking the pot, a positive , but normally doesn't use much of the pots 270 degree rotation, but once setup has produced good results , @bsft cam advise on that he has used them in the past.

@monicamary : A good place to start is the FAQ! ;-)

How to connect potentiometer?
http://www.xsimulator.net/community/faq/how-to-connect-potentiometer.13/

@monicamary , heres a photo of what @eaorobbie was saying
http://img222.imagevenue.com/img.php?image=976312115_potsetup_122_685lo.jpg

Good pic @bsft ! FAQ updated!