Custom Embed Video Thumbnail

Hi ReadyMag friends!
I am a newbie and trying to figure out customizations.
I am looking to make a page of embedded videos as a portfolio, but I would like to customize the the thumbnail image. I don’t want to use the one that automatically shows up on youtube.

If you are using the Video widget, you can also try the default thumbnail option. Basically, it allows you to upload your own image will be placed on top of the video with a play button.