My github workflow

Select branch e.g. master branch. the current branch is called HEAD:

git checkout master

check HEAD:

cat .git/HEAD

modify the code then commit:

git commit -m "leave some note here"

we might want to undo commit:

git reset --hard HEAD~1

or undo to specified commit:

git reset --hard commit_sha

check your local branch with the remote:

git status

push the local commits to remote branch e.g. remote name "origin", branch name "master":

git push origin master

more common command check:

git help everyday