How to configure Full-strict SSL with gh-pages?

Somebody please help me to setup the cloudflare full-strict ssl with github-pages!:worried:

Create the appropriate CNAME on your Cloudflare DNS tab (github.example.com IN CNAME example.github.io). Set the DNS entry to :grey:. Add the custom domain to your Github repo, and wait.

Once you are happy that the GitHub certificate is active, you can set the “Enforce HTTPS” option in GitHub Pages. Assuming your domain in Cloudflare is already Full (Strict), you can just change the DNS entry to :orange: and you should be finished.

I will try that!

It shows is improperly configured! Error…
But I have added the CNAME!