Go to My Grid and click on “more options” in the top right corner of your video of your context menu, and choose duplicate.

You will be asked if you'd like to make a copy. 

If you have in-video questions or captions that you would like to keep from the original, select the appropriate checkboxes.

Choose Duplicate

Your video will upload with the title “copy of [video title]” on your grid. The new copy will have a new URL.