Recording a video of yourself playing a computer game is fairly simple. The biggest hindrance to you aside from knowledge will be your hardware as recording the video can put some stress on the system. If you are able to run modern games on your PC you shouldn't have to much trouble recording a demo.
First you need to choose a recorder that you will use to capture the video. Personally when I want to record I use a program called FRAPS. The other one I have used is called Game Cam. Which one you choose is a matter of personal opinion.
There is a free and a paid version of FRAPS. The free version will suffice in most instances and works just as well as the paid version. Differences between the two are as follows -
- Length of clips
- Full Version - Unlimited
- Unregistered Version - 30 seconds
- Watermark
- Full Version - No
- Unregistered Version - Yes
I won't get into the details of exactly how to use the program as it is very dependent upon the system you will be running it on. One thing to keep in mind is that FRAPs records in raw data format. Meaning there is no compression (you'll need a program such as
virtual dub to handle compressing it).
If you'd like to take a look at what FRAPS is capable of I've retrieved a bunch of search results from www.youtube.com In the meantime take a look at this video that someone other than me recorded. You'll be able to get an idea of what FRAPS does from it.