1. Fork repository someone/coolproject to dvanic/coolproject.
2. Now clone it down to your desktop:
git clone email@example.com:dvanic/coolproject.git cd coolproject git remote add upstream firstname.lastname@example.org:someone/coolproject.git
3. Make some changes
4. Then, when you want to incorporate the changes the primary developer has made:
git fetch upstream git rebase upstream/master
The last command interleaves your commits with theirs chronologially, thereby reducing the number of branches in the final project repository.