Adding music or video
There are two ways to add video or music to your blog: (1) You can upload it to your blog if it is smaller than 48 MB or (2) You can embed video or music that is already hosted online (on YouTube or Vimeo, for example). For this option, skip to step 2. Since audio and video files are very large, it is preferable to embed content already hosted online so that you do not run the risk of exceeding the size limit allocated to your blog.
1) I have to upload the media (Please note: your file must be smaller than 48 MB). On the New Post screen, click the Add media button corresponding to your media type.
On the window that appears, click Choose File, browse for the file on your computer, and Upload. A few more fields will appear:
Fill in any information you’d like, and click Insert into Post (not Save all changes!)
2) The media is already on the web. If your media is already on YouTube or some other website, the easiest way to put it on your site is to copy the URL of the video (for example, http://www.youtube.com/watch?v=81-DexIo22o) and put it on its own line in the post or page text editor, as shown below. When you publish your post or page, it will show up as an embedded video or audio clip.
Please note that you should use the URL (copied and pasted from the top of your browser window) rather than the embed code (which YouTube displays in a text window below the video, as per the image below). WordPress will not display the video correctly if you use the embed code, but the URL will work for most themes.
Sometimes video embedding is disabled for YouTube videos. If the video displays only as a link and will not embed, you can check by clicking on the Share button on the YouTube video page. A message will display that embedding is disabled.