Which Dragonfly you have? The Walkera #4, GWS mini-dragonfly or others, the #4 4in1 has a tiny hole next to the red LED light, you can use a tiny screw driver to adjust the pot inside, clockwise to increase the gyro gain, the GWS one use either PH-1 or PH-3 mixer/esc board, there's 2 pots to adjust, one for gain and the other one for prop, it's a little more work and you have to read the manual.