It is best to employ a proffesional to draw it up and submit. Needs to be worded properly, too broad a description could be dismissed by a rival and too close to your idea may be bypassed with a simple alteration to the product.
Could easily be �15000 to get most world patent and it takes time.
Then someone in China will totally ignore it and their authorities will do nothing. You then have to chase all the individual importers through the courts.
Hope it's a good idea and good luck. Don't mean to be so negative.