Exposure bracketing is useful for shooting frames for HDR images, or for situations where you’re just not quite sure of the correct exposure and there’s no time to experiment. You press and hold the BKT button and turn the rear dial to choose the number of frames and the front dial to change the exposure increment.
That’s fine, but it’s easy to lose track of where you are in the exposure sequence and accidentally frame up a new shot when you haven’t finished the exposure series for the one before.
The solution is simple – switch the camera to continuous shooting mode first – either CL or CH mode will work fine. Now press and hold the shutter button – the camera will take however many bracketed exposures you’ve programmed in (3 or 5, say) and then stop automatically.