Here is how to setup a fresh clone of a git repository so that it pulls changes from an upstream, but only pushes by default to another repository (usually, your own fork of the project).

I use the fish shell. If you use Bash or Zsh it should be straightforward to define these variables in your environment.

set gituser logc
set gitproject chat
set gitorg NacionLumpen

And this is how to setup the clone:

git clone git@github.com:$gituser/$gitproject.git
cd $gitproject
git remote add upstream git@github.com:$gitorg/$gitproject.git
git remote rename origin fork
git fetch upstream
git branch --set-upstream-to=upstream/master
git config remote.pushDefault fork

As always with git, it is trivial, if your name is ‘Linus’ :)