Can't create new Selector

I've been trying to scrape youtube but it hasn't been working. I created a sitemap, then tried to create a new selector, but it won't let me press down on the select button under selector and I can't press anything on screen.It says click on screen to enable hotkeys which I do and then it defaults to element preview. Then if I close down the developer tools it then lets me highlight videos and press done but then the developer tools window is gone so I can't save my selection