I'll make it easy and with a little fun for you!
First -lets assume that the winding crown of your watch is the one of the weels fitted on the car.
Imagine the car which is driving across your watch dial from point 6 (six o'clock) to point12 (twelve o'clock).
Which way the weel of the car is turning?
So, the winding of the watch is executed exactly in the same direction as the weel turn of that car when it goes from point 6 to point 12.
When you wind the watch in that direction, the winding pinion and the clutch wheel (both are parts of setting gear) gets engaged and through the gears turns the barrel which is housing the mainspring.
When you turn the winding crown in opposite direction, the winding pinion and the clutch weel gets disengaged due to the specially angled weel teeth and no action in the setting gear is taken. All you hear is just a rapid clicking sound when the wheel teeth are jumping over each other.
I hope this is Fixya.

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