I've found useful to have a step by step reference guide to work with Git with most used commands, feel free to update it with useful information you may find interesting too.

If you don't have Yii yet

$ git clone https://github.com/yiisoft/yii.git

start your project (being at root folder)

$ yii/framework/yiic webapp myproject
$ cd myproject

initialize git

$ git init

make git add empty directories to the repository

for i in $(find . -type d -regex ``./[^.].*'' -empty); do touch $i"/.gitignore"; done;

(source https://gist.github.com/18780 )

Adding a yii extension repository inside your repo at a specific path (e.g. we will add https://git.gitorious.org/lightopenid/lightopenid.git in 'protected/extensions/lightopenid')

git submodule add https://git.gitorious.org/lightopenid/lightopenid.git protected/extensions/lightopenid

This creates the file .gitmodules in your root folder which tracks all your modules data.

if for some reason (older git versions, cloning from another location) you end up with an empty directory where a foreign repository should be:

git submodule update --init

should fix it. Then you can update your repository and external ones with:

git pull && git submodule update --recursive

To remove a submodule:

git rm --cached protected/extensions/lightopenid

Edit .gitignore file in root folder and add dirs/files you don't want to be in git repo Use ! to negate the pattern:

assets/*
!assets/.gitignore
protected/runtime/*
!protected/runtime/.gitignore
protected/data/*.db

Make your first commit

git commit -a "Initial version"

If you want to add your forked repo from github ( i.e.: git@github.com:marcanuy/Comments-module.git ) from another repo (i.e.: git://github.com/segoddnja/Comments-module.git) to the extensions directory, then:

git submodule add git@github.com:marcanuy/Comments-module.git protected/Comments-module
cd protected/extensions/Comments-module
git remote add upstream git://github.com/segoddnja/Comments-module.git

Then every time you wish to get latest updates from the original repo you should do:

cd protected/extensions/Comments-module
git pull upstream master

Now you are ready to go!