It really is a bit tricky without a dyno, but make sure you have installed it correctly, have taken out the plastic plug from the "unused" port on the solenoid and then try increasing the set boost and using peak function to see what you've hit.
use the gain to stop it spiking and then check its not overboosting again. this is quite hard to get right as you haven't got a numnber to start from really. you will not get a very good result on the road
if your dumb enough to do it on the road, you can set the limiter safety thing up to save you before playing around. if you dont crash, you will either get booked or blow the engine but yeah here is how to do it for the time being. might be better to do it with another twit in the car with you so you can watch the road and he watches the boost.