In your sources branch, which is the main branch for writing creating posts, create a CNAME file in the sources directory.

vim source/CNAME

your-domain.co.uk

Then check-in and deploy

git add source/CNAME
rake deploy

Point your domain to github pages:

A record pointing to 204.232.175.78

I also redirect www. to the non-www url

CNAME record for www.example.com to example.com

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