The first thing you need to do is open up the "database.yml" file and edit it to use the correct usernames, passwords, hosts, etc... that are appropriate for your environment.
You will also need to make sure that you start/install the database of your choice.
Ok, so you've edited the "database.yml" file and started your database, now use:
$ buffalo pop create -a
To run the application use:
$ buffalo dev
Congratulations! You now have your Buffalo application up and running.