Instead of uploading files to our server, we recommend that you upload to a third-party site like YouTube and then use the easy embedding script it gives you.
You can get this embedding script by clicking the share option for a video and choosing the embed option. Copy the embed code.
Next, go to the page on your Site Map where the video will be added. Click the Add Content button where the video should go and choose the Raw Code content type.
Finally, paste the embed code into the raw code source box and give the video a name/title before saving.