Adding your SSH key to GitHub or Bitbucket, will allow you to deploy from a private repository and enable seamless repository access. Just follow these steps:
Step 1 - Generate an SSH Key
Go to Websites → Manage. In the left sidebar, search for GIT and click on it:
Next, click on Generate Key:
Once generated, copy it in order to add it to your GitHub or Bitbucket account in the next step.
Step 2 - Add the SSH Key
Check the instructions according to your preferred repository service:
GitHub
After logging into GitHub:
Click your profile photo and select Settings
In the user settings sidebar, click SSH and GPG keys
Click New SSH key or Add SSH key
In the Title field, add a descriptive label for the new key
Paste your key into the Key field
Click Add SSH key
If prompted, confirm your GitHub password
Bitbucket
After logging into Bitbucket:
Go to View Profile
Click on Settings.
Go to the Access Keys option and click on Add key
Paste your key and save the changes