How to update a local git repository if your forked version is not up to date with the original repository
git remote add original repository-address
View the local remote-origins git remote -v
git merge original master
git push origin master
For instance I want to review a pull request on https://github.com/aschplatform/asch with the number #188
# clone repository
git clone https://github.com/aschplatform/asch`
git fetch origin pull/188/head:pull_188
git checkout pull_188