There are tons of tutorials in the internet on how to do that.

But for your interest let me help you..

1. Before anything else, either you are using a MAC or Windows, you should be able to install first the USB drivers for your POD HD500. You can do that by downloading LINE6 MONKEY program first from line6.com then let the monkey guide you for the installation of the latest drivers, firmware updates for your POD HD500 and POD HD EDIT program.

2. After you installed all the necessary drivers, now its time to install a recording program that recognizes your installed drivers. To name a basic and easy program, try REAPER. Its easy but its really packed with features.

3. After installing REAPER. Launch REAPER and go to Options>preferences> and go to Audio Device settings. You should be able to see that the driver used for recording is ASIO POD HD500

4. Now that everything is configured, try to insert a new track... go to TRACK>Insert New track. At the left most part of the track you will see a small button labelled  "ar".

That stands for ARM for recording. By now, you should be able to see the audio meter peaking up as you play notes from your guitar. This shows that you are good to go.

5. Press the record button and see how magic happens!

6. Congratulations to your new  HD500

7. You may want to search in youtube for more videos on how to do this. look for youtube username alexromachado  he has tons of REAPER tutotials using POD HD500.=)