it's easy... but may i ask why you'd want to spit flames?
the easy route, if thats your only goal, still requires your car to be emissions exempt.
it involves three things, a test pipe, a 4 bar fpr, and a tune that gives you two-step (ignition cut based launch control)
i actually provide all three, if you're interested, PM me.
since running a test pipe is not street legal if your car isn't emissions exempt, a high-flow race style catalytic converter can be installed to help reduce the chance of clogging/overheating from the fuel dump that happens with two-step. if you have no concerns, the rear o2 can be removed with the tune so a test pipe can be run without the rear o2 sensor.