how to fork in bitbucket website code example
Example: how to fork from github to bitbucket
$ git clone https://github.com/cakephp/cakephp
$ cd cakephp
$ git push [email protected]:mg/cakephp.git master
$ git clone https://github.com/cakephp/cakephp
$ cd cakephp
$ git push [email protected]:mg/cakephp.git master