IF YOU DISLIKE THE SENSATION OF FLYING DURING TURBULENCE, SIT OVER THE WINGS OF THE AIRCRAFT.
The feeling of climbing or descending initially is the result of the turbulence, followed by the opposing direction as the aircraft reacts to it. These changes feel more drastic when sitting at the rear of the aircraft, as whilst the aircraft begins to climb, the tail moves downward and you will have the unusual sensation of being pulled out of your seat. If you sit over the wing, the aircraft pitches around its centre axis, resulting in a smaller sensation of movement as a passenger.
The aircraft will rarely change altitude by any more than 50 feet, which honestly is insignificant in proportion to its cruising level of around 37,000ft. Although to some it may feel that way, I promise that the aircraft isn’t falling out of the air, and the change of wind direction is never great enough to result in the aeroplane to stop generating its lift that it creates to fly!