· Sign up and create a GitHub account in www.github.com.
· Download git from https://git-scm.com/downloads and install it in your system.
· Open the project in android studio and go to File -> Settings -> Version Control -> Git.
· Click on test button to test “path to Git executables”. If successful message is shown everything is ok, else navigate to git.exe from where you installed git and test again.
· Go to File -> Settings -> Version Control -> GitHub. Enter your email and password used to create GitHub account and click on OK button.
· Then go to VCS -> Import into Version Control -> Share Project on GitHub. Enter Repository name, Description and click Share button.
· In the next window check all files inorder to add files for initial commit and click OK.
· Now the project will be uploaded to the GitHub repository and when uploading is finished we will get a message in android studio showing “Successfully shared project on GitHub”. Click on the link provided in that message to go to GitHub repository.
source : https://stackoverflow.com/questions/37093723/how-to-add-an-android-studio-project-to-github