Go to emport/import
then to Export Unencrypted
then select private key format you want
look at the coloum
after your address there is word priv" ...
that is your private key
Also make sure that you are using the computer version. You wont be able to do this if you are using the mobile version of the blockchain
it is much faster than that, you only need to click on "paper" a window will appear with your private key, that's it
maybe they improved it since that video is a bit old...