Here are some useful Git commands..
Clone repository
git clone path_to_repository
Pull and overwrite existing changes
git fetch --all
git reset --hard origin/master
Set Windows integrated authentication
git config --global credential.http://servername:port.integrated true
Store credentials in repo config (WARNING: stores credentials in plain text)
git remote set-url origin https://<USERNAME>:<PASSWORD>@github.com/path/to/repo.git
Store credentials locally in credentials store (WARNING: stores credentials in plain text
git config --global credential.helper store