Multiple Github accounts on one machine

Step 1. Generate an SSH key

cd ~/.ssh
ssh-keygen -t ed25519 -C "your_email_address"

Follow the prompts and enter your github username, e.g. github_username

Step 2. Add SSH key to SSH Agent

ssh-add ~/.ssh/id_ed25519_github_username

Step 3. Copy the SSH public-key to Github

~/.ssh/id_ed25519_github_username.pub

Step 4. Add a host entry to the ~/.ssh/config file

Host github_username
  HostName github.com
  User git
  IdentityFile ~/.ssh/id_ed25519_github_username

Step 5. Config your remote

git remote add origin git@github.com-<your-username>[:owner-user-name]/<the-repo-name>.git

Step 6. Config git user.name and user.email

git config user.email "your email"
git config user.name "your name"

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