Remove all files fro ~/.ssh folder
ssh-keygen -t rsa -C "rajan@punchouty.com"
Give empty passphrase. Two files be created in ~/.ssh folder
eval "$(ssh-agent -s)"
ssh-add ~/.ssh/id_rsa
pbcopy < ~/.ssh/id_rsa.pub
In www.github.com add key => Go to Setting > SSH and GPG keys > New SSH key