Buffeting is a high-frequency instability, caused by airflow separation or shock wave oscillations from one object striking another. It cause by a sudden impulse of load increasing. It is a random forced vibration.
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The pilot should start recovery when buffeting begins, by simultaneously lowering the miniature aircraft to the horizon (or as required in the AFM) on the attitude indicator and adding maximum allowable power. Maintaining the level flight attitude causes the airspeed to increase.
Every aircraft has its own spin characteristics, but most will go through an early incipient spin where rate of roll and yaw are fluctuating and the pilot may feel some airframe buffeting. If action is taken at this point the recovery will be almost instantly.
Do not use ailerons, keep the ball centered - or the wings level with your rudder. Do everything gently and stay relaxed. Keep one eye on the air speed and the other on the ball (or horizon and wing tips). Notice everything: buffeting, stick back pressure, control stops, ...
See also: What is the meaning of Buffet, Speed, Flight, Aircraft, Lift?