Go to the video you want on YouTube.
Under the video you will see a Share button. Click that.
A new little menu pops up that has Share, Embed, Email.
Under the Embed code, click Show More.
Change the Video Size to Custom Size.
In the first box next to that, type 480 (this is the width of the video that best fits a blog post).
The height box automatically fills in.
Make sure “Show suggested videos when video finishes” is UNCHECKED.
Scroll back up the page a little and copy the Embed Code that is there now. Highlight and copy that code.
Inside your blog Dashboard, this will work whether you are creating a new Post or a new Page.
Create a New Post (or Page).
Click on the Text tab on the right side of the post window.
Paste the Embed code into the post window.
Now you are ready to either Publish, Preview, or add more text to it.