Want to use Twitter Cards in my website


hi, i want to use twitter card.
when i input my website in Card validator,
result - “INFO: Page fetched successfully
INFO: 11 metatags were found
WARN: Not whitelisted”

what whitelist???

i already create twitter app at "https://apps.twitter.com/"
my app name "MS_b"
and my site “http://middlestreet.kr/

how can i use twitter card??


There is no Twitter Cards markup on that site, so the validator cannot render a preview and Cards will not show up.

Note, you do not need a Twitter App in order to use Cards.