1. checkout users to ./users 
1.1 if needed, checkout branch to be tested
2. checkout simpletest to ./simpletest
3. tailor users_config.php to your local mysql settings.
3.1. It is best if you login to your localhost mysql root and execute:
    create database startup_test;
    grant all privileges on startup_test.* to 'startup'@'localhost' identified by 'startup';
    flush privileges;
4. cd users/tests
5. make test