If the child happens to wet or soil the bed at night help the child to be cleaned up gently, have the sheets on the bed changed and put the child back to sleep. During potty training if and when accidents like these happen and you start to loose your patience and get angry it is no way going to help in the progress of toilet training.
Do not ever punish your child for any toilet training accidents which may occur, as it will only end up hurting the child's self-esteem and bring down his or her confidence level.
Toilet training accidents can happen up to 6 months after the child has started toilet training and it is normal to expect such eventualities by the parent. If you see any improvements then you can be rest assured that your toilet training is going on smoothly without any hitch.
If you find that your child is having more accidents than having smooth experiences while toilet training then you be rest assured that your child is not ready for toilet training as yet. Wait for another 2 or 3 months when the child is more receptive before you embark on toilet training again.Toilet train your child only when he or she is ready to be toilet trained otherwise you will find that the child will put up a lot of resistance if he or she is forced to toilet train. Come to terms that it is absolutely normal for a child to have toilet training accidents and try not to make a big issue out of it.
There are some children who would refuse to be toilet trained and this warrants that the parents sit back and analyze what is making the child refuse to be toilet trained. Be loving and gentle with your child while your toilet train them as it is patience coupled with reassurance that goes a long way to help the child to be toilet trained eventually.
You can read articles written by other parents on how they toilet trained their kids. On the internet you will find plenty of websites that cater to toilet training for children. Here you will be able to learn a lot of things about toilet training. You can also read articles on how other mothers coped with toilet training accidents when they toilet trained their children.