You need to give more information. Is it a fixed-pitch or collective-pitch? One main rotor, or counter-rotating rotors? The trim controls on the radio are probably what you're looking for. Trimming each time you use your heli is essential. Take off, get the heli out of its own ground effect (2 or 3 feet off the floor), then trim. After that, it should fly well. If the rotation is too fast for trimming, a physical modification might have to be made. If it's a single rotor heli with a tail rotor, tweaking the angle of the tail will help. Twist the tail gently and let go, if the tail is tipped just a few degrees off, it can effect the heli. If it's a counter-rotating heli, one of the main rotors may be damaged (bent, chipped, cracked, etc) and not working as strongly as the other rotor, causing the rotation. You'll probably have to get a replacement rotor in order to fix that.