Connect your electric guitar to your computer. There are a number of methods for doing this, each with their own advantages and disadvantages. If you do not have an amplifier or USB recording equipment and are unable to obtain this equipment, you will need to get an adaptor (1/4" to 3.5 mm female/male) and connect it to the output end of your instrument cable. This will allow you to connect your guitar directly to the "Line In" jack on your computer. However, unless you have active pickups on your guitar, the signal into your computer will be weak and poor in tone. If you have access to an amplifier or preamp unit, you can just run the guitar signal through the amplifier, connecting the amp's output jack to the computer's "Line In" jack with a 1/4" to 3.5 mm male/male cable. If you choose to use a USB recording device, simply connect your instrument cable to the device's input jack and plug the USB into your computer. Make sure to connect your guitar to the input end of the instrument cable.
Purchase or download software to use in your looping station. A vast number of commercially available recording software programs -- such as Ableton Live, Reason, GarageBand, Sony Acid, FruityLoops, and AudioMulch -- include looping features. If you are unable to obtain a copy of commercial software, a limited number of freeware choices are available for download as well. Windows users can use Sony Acid Xpress, the free limited version of Sony Acid. Mac users can download SooperLooper or Loop Editor Plus, two freeware looping applications for OS X.
Record and loop. If you have commercial recording/looping software, read the documentation included for instructions on how to use the loop functions. If you downloaded an application, check the read-me file or the software's website for help on using the loop function. Most looping software is fairly self-explanatory to musicians who are familiar with digital loopers. Almost all looping software has the same basic controls, including a record loop button, loop length control, loop tempo control, overdub control, loop decay control, reverb control, echo control, and a number of other controls which can be adjusted to fit the musician's specific needs. Experiment to see what works best.