The bloody show happens when the mucus plug comes off. It means your body is now prepared and it's a sure sign of impending labour. Your contractions, at an average, should start within the next 12 hours. However, every woman is different and so is every labour. That is why, yours could be shorter or longer than that. After the bloody show, however, it doesn't take long for the contractions to begin. It is safe to say that you should start preparing yourself for labour. Remain active, eat little easily digestable snacks like sadnwitches and don't tire yourself too much.
The bloody show happens when mucus plug comes off. It's one of the most important signs of inpending labour. When that happens your labour might start in about 12 hours. However, every woman's labour is different and it might take you a shorter time than that. It could also be another 24-48 hours. What it means for sure is that your contractions will be starting soon, very soon.