官方帮助文档：
https://help.github.com/articles/create-a-repo
登录github，点 New Repository.如下面图所示，
新建一个文件，初始化本地库git init,如下：
Step 1: Create the README file
In the prompt, type the following code:
mkdir ~/Hello-World
# Creates a directory for your project called "Hello-World" in your user directory cd ~/Hello-World
# Changes the current working directory to your newly created directory git init
# Sets up the necessary Git files # Initialized empty Git repository in /Users/you/Hello-World/.git/ touch README
# Creates a file called "README" in your Hello-World directory
提交自己的文件到库中，用到git add ,git commit命令，如下：
Step 2: Commit your README
Now that you have your README set up, it's time to commit it. A commit is essentially a snapshot of all the files in your project at a particular point in time. In the prompt, type the following code:
git add README
# Stages your README file, adding it to the list of files to be committed git commit -m 'first commit'
# Commits your files, adding the message "first commit"
提交自己的代码到github上，
1，先添加远端，git remote add xxxxx
2.push
Step 3: Push your commit
So far everything you've done has been in your local repository, meaning you still haven't done anything on GitHub yet. To connect your local repository to your GitHub account, you will need to set a remote for your repository and push your commits to it:
git remote add origin https://github.com/username/Hello-World.git
# Creates a remote named "origin" pointing at your GitHub repository git push origin master
# Sends your commits in the "master" branch to GitHub
