However, there are some things you need to know if you are considering doing work as a TV extra. If you want to learn from the experience of being a TV extra, pay attention to everything... especially if you are working as a stand-in. Pay attention to the process. Instead of talking with other extras, stand-ins or whoever else is around, watch the director, the actors, the crew, etc. Try to pick up as much as the terminology as possible when you work as a TV extra. When the time comes for your first role on a major film or television show, you'll know what to expect, what is going on, and you'll be better prepared for the experience.
As a TV extra, don't expect to be prominently seen in the final
product. There is a reason why a TV extra is called "background."
If you are doing TV extra work with the hopes of easily being
seen on TV or in a film, it's probably not what you want to do.
Most likely you'll catch a quick glimpse of yourself somewhere
in the background of a shot.
Other than that, have fun and enjoy the experience of being a TV extra. Do TV extra work if you are interested in how the process works. You'll meet a lot of great people and probably make a few friends along the way.