Just for starters........The pg-03 I have has only 2 adjustments screws.
1. The first thing I always do is start with the setup adj. screw on the left and turn it all the way left.
2. Then add just enough throttle in order to activate the tail rotor without getting the main rotor to spin, or better yet, just disconnect the main motor from the control board altogether momentarily.
3. Grab the heli's boom by the hand adding yaw to the right with your hand. the gyro will kick in in order to try to fight the tails movement in the counter clockwise direction, because this is the normal tendency of heli's behavior when the main rotors are spinning in the clockwise direction (torque reaction).
4. In small increments, slowly turning the setup screw to the right almost to the mid gain. This screw adjusts how strong of kick (forcefulness) the gyro puts out to the tail. Mine is adjusted to where it barely changes colors from red to green or green to red, if i recall correctly. you don't want it to be too forcefull when the gyro kicks in to keep the tail stable. The amount of yaw you want to add is about the same amount of yaw your heli's main rotor produces when the main rotors are spinning. But it depends on how agressive you plan to fly. You will have to decide your preference.
5. Once the setup screw is is adjusted as close as possible to simulate the normal yaw your heli produces when are you add throttle, it is now time to adjust the fine adjustment screw (the one to the right labeled 'gain'). Simple plug up main motor again and start with this screw in the middle. This screw adjust the fine movement sensitivity. You have to adjust it to your liking. If the heli's nose tends to turn right while you hover or fly, then turn the gain in the negative direction because this means that you are too sensitive (too much gain).
6. If the heli tends to turn left in flight, it means you have increase the gain screw to the right or positive direction. You will know when you have it correct because you should almost be able to fly the left stick hands free, or atleast close to it.
These are merely the steps that I take with that gyro. I even had my FP hummer so stable, that i could take my hands of of the transmitter for a few seconds in a hover.
Here is a video of my old FP hummer. I use the same method for my stock CP hummer. I hope this helps.