If you want to use your camera your phone might be the easiest. If you have an iPhone, which has an application called iMovie on it. Take a look at a video (below) which shows the easy way to make videos through this application. Happy video making!
You may want to use your laptop or computer camera and if you do, you may want to use an application freely available on the Internet.
See attached video on Screen-o-matic. below.. Note: to use many of the editing features you will need to pay, but you are able to add royalty free music and cut ends of the your video, if needed.