From the announcement:
Want to give Brushfire a try without having to spend a dime? Use Paperfire along with the Brushfire Quickstart Rules to get the basics of the game down before committing to it. This PDF includes paper cut outs of the models included in the Aquitar and Mare-Civitas warband starter sets, just print, cut, and play!
You will of course need a friend, or a particularly skillful Dog to play with, a table to play on, and a handful of D10 dice.