Create a new orphan branch, use three ways. A orphan branch like Github Pages(create a gh-pages branch).

orphanBranch.sh

#1. Hack ./git/HEAD file

echo ref: refs/heads/orphan_branch_name
git rm -rf .
# .............. # add file ...   commit file ... 

#2.Use --orphan parameter

git checkout --orphan orphan_branch_name
git rm -rf .
# .............. # add file ...   commit file ... 

#3.Use git symbolic-ref command

git symbolic-ref HEAD refs/heads/orphan_branch_name
rm .git/index
# .............. # add file ...   commit file ...