In Terminal:
ssh-keygen -t rsa -f "id_rsa_<new account name>" -C "<email of new account>"
ssh-add ~/.ssh id_rsa_<new account name>
Edit ~/.ssh/config
:
Host <hostname for new account>
HostName github.com
IdentityFile ~/.ssh/id_rsa_<new account name>
Clone repository:
git clone git@<hostname for new account>:<github account name>/<repository name>.git
cd <repository name>
git config user.name "<new account name>"
git config user.email "<email of new account>"