If you want to begin a .UK domain transfer to your account you'll need to contact your current domain registrar and ask them to set your domain IPS tag to TUCOWS-CA.
Once the tag change is completed, contact us to complete the transfer process.

If the current Registrar is unable or unwilling to make the change, please contact Nominet directly (http://www.nominet.org.uk) and they will help make the change.