test transactions

Looking at the five bells demo

https://github.com/interledger/five-bells-demo

I am able to get the 8 ledgers up and visualized.  I can also see them
using sqlite, and access each account individually.

The README says

"It allows you to very quickly spin up a complete Interledger network *and
do test transactions*."

It doesnt say how to do transactions.  Is there any guide?