title: Git: How to push to someone's fork?
body: <p>I work for an open-source project and forked it already. Someone has forked it too and has been working with some interesting ideas which won't be pushed to origin soon. I want to help him thus I cloned his fork to my computer. However, I can't push directly my work to his fork. I can't fork him either since I have a fork from origin already. What should I do? Thanks</p>