Keeping a fork synced with the origin repo

1. fork upstream_repo_url
2. git clone origin_repo_url
3. git remote add upstream upstream_url
4. git remote -v
5. git pull upstream dev
   - git fetch upstream
   - git checkout dev
   - git merge upstream/dev
6. git checkout -b dev_01
   (modify code...)
7. git push origin dev_01
8. pull request