Synchronize with remote branch (master) - fetch remote code and merge with local (git fetch + git merge)
git pullUpdate local version to master branch
git checkout masterThe process when updating your fork of someone else's repository is described here. Basically, fetch changes from the original repository (upstream):
git fetch upstreamMerge the changes into local master branch:
git merge upstream/masterPush the changes to your remote repository (on GitHub). Easiest way on Windows is to use GitHub application.