Basic Git Submodule Commands

git_submodule.txt

#Main proj.
#Add a submodule.
git submodule add https://proj.git
#Go to submodule's dir and change to specific branch.
cd submodule_dir
git checkout -b branch origin/branch
#Go back to proj root and push to repo along with the new submodule's new branch.
git add . -u
git commit ...
git push

#Forking proj.
git checkout -b branch origin/branch
#Use the submodule that the main proj is using.
git submodule update --init