First please go through your operating specific instructions available in LINUX.md/MAC.md/WINDOWS.md.
There are a few helper calls that make it easier to use.
If you just want to start up an evironment to test in then there are only one command you need to run.
make start-servers
The frontend will be available at http://www.dev.test
You can remotely connect to the database at db.dev.test:5432